By the cytological study on the neurosecretory cell of supraoptic and paraventricular nuclei in the normal dog with special reference to the relation of the secretory material to cytorganelles and NISSL substance, and following findings were obtained.
1. The most frequently observed form of the neurosecretory cell is a multipolar one, while the bipolar and unipolar cells are rather rare.
2. A few binucleate cells and several cells which show a colloidal inclosed body in the cell nucleus, which are suggestive of an amitosis and of a nuclear secretion respectively, were observed, but their significances could not be confirmed.
3. The most frequently observed form of mitochondria of the neurosecretory cell is rod-like, next, granular, and the filamentous form is exceptional. These mitochondria are often gathered near the nucleus, and in the other areas of the cytoplasm they are scattered evenly, exclusive of the NISSLarea.
4. The GOLGI-apparatus makes a complete or an incomplete network around the nucleus. The network is relatively well developed in the area of the cytoplasm opposite to the nucleus, which usually takes a more or less excentric situation.
5. In the dog too, the neurosecretory material is divided, according to its forms and the affinities to dyes, into three types-irregularly formed fine granules, spherical granules and irregularly formed larger masses.
6. By double- or re-staining methods, the relation of the neurosecretion findings to the forms, amounts, and situations of mitochondria and of GOLGI-apparatus has been studied, but no definite result could be obtained. But, as the fine granules are most frequently observed in the cytoplasmic area near the nucleus where usually many mitochondria and a well-developed GOLGI-apparatus are found, it is presumed that mitochondria, with their enzym system, and GOLGI-apparatus, with its chemical components, might have intimate relations to the production of the secretory material.
7. Near infundibulum in pars ventromedialis of supraoptic nucleus, several cells which have a deeply stained, pycnotic nucleus are frequently observed. Such a cell is considered to be degenerating, also by the form of nucleus and the findings of mitochondria. As, on the other hand, such a cell is stained by CHP method as a mass of gomoriphil substance, the occurrence of holocrine secretion as a mode of neurosecretion is presumable.
8. The NISSL substance of a neurosecretory cell differs in form, distribution and amount according to the cell size. Two types are observed on the amount of the NISSL substance in smaller cells-in some cases they are rich in NISSL substance and in other cases poor. But, in both cases the neurosecretory material is scanty. In moderate-sized cells, it is typical that massive NISSL-substance is located in the perihery of the cytoplasm and powdery formed lie in the central area, and the cell becomes larger as the secretory material increases in it. Larger cells are generally filled with neurosecretory material with a little amount of NISSL-substance scattered in the cytoplasm. By the production and accumulation of the secretory material a moderate-sized cell becomes larger, which returns to a smaller cell by the intraaxonal or extracellular discharge of the granules. And a smaller cell, storing the NISSL substance, becomes larger as the production of the secretory material again takes place in it. Such a functional cycle can be presumed showing interrelationships among the secretory material, NISSL substance and the cell size.
9. In this functional cycle it is presumable that the production of the neurosecretory material occurs at the cost of the NISSL-substance, but not presumable that it takes place by a direct transformation of it, considering above-mentioned findings.

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With experimentally dehydrated dogs, general conditions of neursecretory cells of supraoptic and paraventricular nuclei and changes in the shapes and forms, arrangements, and distributions etc. of mitochondria, GOLGIapparatus, NISSLsubstance, and neurosecretory material were observed.
1. The size of a cell nucleus is enlarged in the dehydrated condition, manifesting hyperactivity of cell function.
2. Intranucleolar vesicles are increased markedly, and taking the irregularization of the arrangement and distribution of NISSL-substance also into account, a change of the mechanism of RNA metabolism is suggested.
3. Mitochondria are observed to grow long rod-like or filamentous and, in addition, to tend to collect themselves in the cytoplasm nearer to the nucleus. It is considered that mitochondria would probably participate in the formation of secretory material indirectly through their enzyme system.
4. GOLGI-apparatus, in the dehydrated condition, are developed remarkably, displaying frequently a complicated network formation. On the other hand, many cells with GOLGI-apparatus of fragmented form are observed. These findings are considered to be symptoms of hyperactivities of cell-functions.
5. Individual NISSL bodies become irregular in shape and form, unequal in size, and confused in arrangement, and massive NISSL-substances appear frequently in the central area of a cell, esp. adhering to the nuclear membrane. These findings are considered to signify a condition where a good many material to be consumed for the production of the secretory granule are being supplied answering to a markedly increasing demand of adiuretin. The condition might be accompanied by the change of the mechanism of RNA metabolism.
6. Of secretory material in the cell, in the dehydrated condition, an extremely small amount of them in fine granular form are only observed scattering in the cytoplasm near the nucleus. This might signify that the secretory material, answering to an increasing demand, is quickly transported to the posterior lobe, with little time to stay in the cell body.
7. Such cytological findings on neurosecretory cells in the dehydrated condition as are described above are considered to show that the production of the secretory material accompanied by some changes, more or less, of the mechanism of RNA metabolism, is in a highly elevated condition.

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The caudal end of the human facial nucleus is on the level of the cranial part of the inferior olive and its cranial end somewhat on a higher level than the lower part of the abducens nucleus. The total length of the nucleus ranges between 4.4 and 4.8mm, a value somewhat larger than what has been reported to date. This discrepancy is perhaps due to the fact that I have taken into account the considerable extension of the caudal and the cranial end parts where the nerve cells forming the nucleus abruptly decrease in number. The length of the main part of the nucleus where the nerve cells are numerous and close-packed is about just 4mm, so that the end parts with decreased cells total 0.4-0.8mm in length. In transverse sections, the nucleus in its median part with densely packed nerve cells measures 2.5-2.7mm in the major and 1.5-1.7mm in the minor diameter.
The nerve cells in the facial nucleus show a rather perceptible group arrangement, but in the case of human facial nucleus, the opinions of the past researchers have been rather a variance on this grouping, for the cell groups are not marked off by fibre capsules, as in the case of cat, and they show varied fusion and partition on different levels. The cranial part of the human facial nucleus is represented as a small round patch of nerve cells on cross sections. About 0.3mm downwards of the cranial end, the tripartite basal form of the dorsal, the intermediate and the ventral groups begins to appear. Toward the caudal part, the nerve cells speedily gain in number, and in some places, the intermediate group is parted into the medial and the lateral subgroups and the ventral group into the lateral, the middle and the medial subgroups. Upon approaching the caudal end, first the dorsal group fades out, then the intermediate group, the caudal end part consisting of an extension of the ventral group alone. The nerve cells also gradually decrease in the end part finally to nothing. The caudal end part amounts to ca. 0.4-0.5mm in length.
As the human facial nucleus is not covered by fine nerve bundles, its boundary is not sharply defined. Consequently, some motor nerve cells wander out into the neighboring substantia gelatinosa, trapezoid body, formatio reticularis etc.
The motor cells in the facial nucleus are rather densely arranged, are 40-60μ in diameter, have several nerve processes each, show concave outline in the parts between the processes and give the virils appearance common to the motor cells in the other motor nuclei. The nerve processes are always smooth-surfaced. The axis cylinders are finer but darker-staining than the short processes and number one per cell usually, but sometimes we see 2 of them emerging form one cell and sometimes a single axis cylinder is found bifurcating. The short processes are filled with weak-staining neurofibrils, are very stoutly formed and are branched out into several rami. Their terminal fibres gradually taper off into sharp points.
The motor nerve cells are usually uninuclear, but some of them are binuclear. The cell nuclei are located centrally in the cell bodies, are round and contain chromatin granules which are very weakstaining, unlike those in vegetative cells, but the nucleoli darkstaining. The content of yellow pigment granules in the motor cells is particularlarly large. The granules are aggregated locally in the cell bodies, but nearly no neurofibrils were found running through these pigment aggregates.
Other nerve cells than motor cells are contained in the human facial nucleus as in the feline facialis (MORITA). The small-sized vegetative nerve cells are less numerous than in the cat facial nucleus and are found in particular frequency in the dorsomedial part of the nucleus. Most of them are spindle-form and contain mostly eccentrically standing nuclei provided with dark-stained chromatin granules, unlike those in the motor cells.

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In the outer half, the upper wall of the bony part of the external auditory canal shows a histological picture similar to that of the cartilaginous part, but in other sides and parts, the picture of the wall is quite different. In the former part too, however, the further we go inwards, the epidermis becomes the thinner, the hair follicles in the corium worse developed and the ceruminous glands in the subcutis the fewer, finally disappearing altogether.
The development of the str. papillare of the corium of the bony part is very poor, so that in some parts it appears as if the epidermis directly touches the str. reticulare. Stratum reticulare is composed of collagenous fibre bundles arranged circularly, but is only very thin except in the outer half of the upper wall of the part, as is also the subcutis containing a small number of fat cells, and its outer surface joins the periosteum of the temporal bone.
The epidermis becomes the thinner, as we go further interiorwards, its str. germinativum being covered by a thin horn plate often with cell nuclei, as found in the tympanic membrane.
The inner half of the bony part is abundantly provided with blood vessels. Beside the venous plexus without smooth muscle fibres extending out of the subcutis into the corium, we find some small veins surrounded by longitudinal smooth muscle bundles. These veins are connected with the capillaries formed subepidermally, and in the outer half, the veins gradually gain in size, but the muscle fibres around them decrease more and more. There are besides some smooth muscle fibres running about circularly in the corium independent of any blood vessels.
The innervation, especially, the sensory innervation, of the cartilaginous part is not much different from that of any common haired skin. That is to say, most of the sensory nerve fibres end in plexus-like terminations poorly developed in the SETO's so-called hair nerve shields or rings in the necks of the hair follicles, while a minor part of them run into the str. papillare and form unbranched and simple branched terminations therein. The quantity of such fibres here is larger than in the scalp, the eye-lid, the belly and the back skin, and is nearly equal to that in the outer genitals and the perineum, but though this cartilaginous part is susceptible to a similar ticklish feeling, it contains no genital nerve bodies or PACINIan bodies.
The outer half of the upper wall of the bony part of the auditory canal is rather similar to that of the cartilagionus part, poorly formed plexus-like terminations being found in the poorly developed hair follicle necks and unbranched and simple branched terminations beneath the epidermis. The quantity of the latter here is larger than in the cartilagionus part.
In the wall of the bony part except in the upper side of the outer half, the sensory fibres are markedly abundant, mostly ending in unbranched and simple branched terminations subepidermally. On approaching the tympanic membrane, the number of sensoy terminations grow still larger, some of their terminal fibres showing the appearance as if running into the epidermis itself, as seen in the skin part of the tympanic membrane. Besides, some branched terminations usually formed by thick fibres are not rarely found adjacent to the periosteum of the temporal bone in this part.

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The author, who has previously investigated the secretory function of the parotid gland cells when histamine in the blood was increased by injections of 3mg of histamine hydrochloride daily for the periods of 1, 15, 30, 45 and 60 days, has now attempted to observe the secretory function of the submandibular gland cells under the conditoin in which histamine increased in the blood and an anti-histamic action of the parotid saliva, which has previously been demonstrated by FUJIE, was perfectly excepted. For this purpose, the author has extirpated the parotid glands totally, because the experimental result in which the remarkable increase of histamine in the blood according to the total extirpation of the parotid glands was demonstrated, has been reported by NAKAO.
It was concluded from the observations on the quantitative fluctuation of the secretion vacuoles in the gland cells, on the form of plastosomes, on the size augmentation of the cell nuclei, on the dilatation of the gland lumen, the intercalated portion or the striated duct and on the contents in them, that the secretory function (the production and the discharge of the secretory substance) of the submandibular gland cells had become active, regardless of the administration of diet, after the extirpation of the parotid gland, and that it greatly resembled the cell function of the parotid gland cells, which the author formerly observed. However the nucleic acid in the nuclei of the submandibular gland cells, which is believed to participate in the compound of the secretory substance in the cells, increased less than in the nuclei of the parotid gland cells. Here it is noticed that the secretion of the former gland cells may differ from the one of the latter gland cells, though the cells of both glands are serous cells of the same kind.
According to these conclusions, it is regarded on the one hand that, if the parotid gland were perfectly extirpated, the saliva secreted in the oral cavity seems to be compensated by the submandibular gland, and on the other hand that, it should not cause wonder if a difference between the parotid and submandibular saliva can be found in the internal secretion theory of the salivary gland (OGATA) and in the anti-histamic action theory of saliva (FUJIE).

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Nerve plexus is formed in the hilus ovarii of dog, but this is far poorer than that in man in development. The nerve elements there consist of numerous thin vegetative fibres and a small number of thick sensory fibres. Perivascular plexus is found along the walls of blood vessels, especially of the arteries in the hilus.
The small nerve bundles running through the hilus into the medulla branch out into finer branches, which ramify and come into mutual anstomisis to form intramedullar plexus. This plexus is also poorer in size than that in man.
Vegetative fibres originating in the intramedullar plexus are found also running into the cortex. These diffuse widely in the cortex and are quite larger in number in dog than in man.
The terminations of vegetative fibres are represented by STÖHR'S terminal reticula in a canine ovary too. For example, the vegetative fibres running along the blood vessels in the ovary, which have been described as ending in free terminations, always pass through preterminal fibres over into terminal reticula, as in perivascular vegetative fibres in all the other parts of the body. The terminal reticula always make ramifications and anastomoses with each other, forming a large system of net-works. They contain SCHWANN's nuclei here and there and stand in tactile control over the supplied cells.
A few vegetative fibres are found running into the tunica albuginea which are well developed in the parts approaching the mesoovarium. These form their terminal reticula in the connective tissue and sometimes directly beneath the germinal epithelial cells in these parts, which however, never penetrate into the epithelial cells. Where the epithelial bladders originating in the germinal epithelium are in good development, the connective tissue between the bladders is very poorly developed, but in some rare cases, terminal reticula are formed in this tissue too.
Nerve supply to the primary follicles in the cortex is richer in the canine than in the human ovaries. Their terminal reticula run along the outside of the follicle cell layer, but unlike in human ovary as described by SAKAGUCHI, they never run into the follicle cell layer.
The nerve supply to the egg follicles in the course of growth and provided with stratum granulosum is also much better developed in dog than in man, the thecae folliculi containing a rather large quantity of vegetative fibres. These also end in terminal reticula and come into control over the connective tissue cells as well as the small blood vessels and the capillaries. A part of the terminal reticula penetrates as far as into the basal layer of the stratum granulosum.
Atretic follicles are rather limited in number in dog's ovaries, and this may be due to the better nerve supply to the egg follicles in dog than in man. Vegetative nerve elements are also found running into these follicles, especially often in company with the newly blood vessels or capillaries. They also end in terminal reticula.
Well-developed terminal reticula are formed in the connective tissue containing blood vessels and blood capillaries in the medullar substance. Fine fibres are also found running into the rete ovarii, their terminal reticula sometimes being formed on the outside of the epithelial cells layer. Terminal reticula are found also around the medullar cords existing especially abundantly in the peripheral parts of the medulla. But the development of the terminal reticula around such epithelial ducts is by no means good and of course no terminal reticulum is found to penetrate into the epithelial cells.
Sensory terminations have been discovered in the ovaries of dog as in man. Here, the trunk fibres, after losing their myelin, end in sharp or blunt points without branching or after branching out into 2 or 3 rami. That is, their terminations are either of the unbranched or the simple branched type, which are formed in the medulla

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Es wurden Exsudate aus der durch die Injektion von Kroton-Olivenöl in die Unterhaut hervorgerufenen Entzündung des Hundes sowie aus den akuten Entzündungen und den tuberkulösen Senkungsabszessen des Menschen nach dem Ausstreichen und Fixieren hauptsächlich nach der Azanmethode gefärbt, um die Ultrastrukturdichte von verschiedenen nichtzelligen Bestandteilen zu untersuchen. Das Exsudat aus des Entzündung des Hundes wurde auch im Elektronoskop untersucht.
1. Bei der akuten wie auch der tuberkulösen Entzündung besteht die unter dem Lichtmikroskop strukturlos erscheinende Grundsubstanz des Exsudates aus verhältnismäßig weniger dicht vorhandenen Molekülen und Micellen. Die Pjs-SCHIFF-Reaktion tritt bei ihr positiv ein, aber die Metachromasie mit Toluidinblau kaum, und die FEULGEN-Reaktion fällt negativ aus. Die körnig-schollig und fädig geformten Gebilde im Exsudat sind von engeren Gefügelücken, geben keine Pjs-SCHIFF-Reaktion, werden zuweilen schwach metachromatisch gefärbt und bieten positive FEULGEN-Reaktion dar. Alle diese Beschaffenheiten sind besonders gut bei kalten Abscessen bemerkbar.
2. Wenn man die zeitlichen Veränderungen der nichtzelligen Bestandteile des Exsudates der experimentell erzeugten Entzündung des Hundes genauer untersucht, so sieht man, daß sie im Anfangsstadium fast aus strukturloser Grundsubstanz besteht, aber schnell mit vielen freien Zellen durchsetzt wird, welche später zerfallen, so daß das Exsudat mit den alternden Zellen und körnigen und scholligen Schlacken angereichert wird. Das molekulare Gefüge solcher Zerfallsprodukte wird im Lauf der Zeit aufgelockert. In der Zeit der Abheilung werden sie immer geringer.
3. Das Exsudat des kalten Abscesses des Menschen ist arm an geformten Gebilden, welche sich in der Regel durch weniger dichtes molekulares Gefüge und stärkere Basophilie charakterisieren.
4. Im Elektronoskop läßt sich konstatieren, daß im Anfangsstadium der akuten Entzündung unter den Teilchen von 5-100mμ Größe die von 6-15mμ Größe am zahlreichsten vorkommen, aber mit dem Fortschreiten der Entzündnng kleinere Formen von 6-10mμ Größe vermehren und im Stadium des Abklingens der Entzündung sich wieder die Formen von 6-15mμ Größe vermehren, welche häufig eine Tendenz zur Kettenbildung zeigen.

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1. Die Aorta ventralis zwischen dem Herz und den Kieferarterien des Goldfisches, eines Knochenfisches, gehört zum elastischen Typus der Arterien, indem in ihrer Media sich die elastischen Elemente gut entwickeln. Dank diser elastischen Elemente kann das Gefäß die vom Herzen direkt geleitete periodische Blutdruckschwankung weitgehend ausgleichen. Während des Heranwachstum des Tieres vermehren sich und verdicken sich die elastischen Lamellen, und zugleich erscheinen interlamelläre elastische Fasern immer mehr. Die Intima wird wegen der Vermehrung der längslaufenden Muskel- und elastischen Fasern dicker. In der Adventitia vermehren sich die Kollagenfasern.
2. Die Aorta dorsalis, die das Blut der Kiemenarterien sammelt und kaudal läuft, unterliegt keiner großen Blutdruckschwankung und gehört zum muskulösen Arterientypus. Die elastischen Elemente in der Media ordnen sich bei dem Knorpelfisch Dasybatus akajei und dem Knochenfisch Schwarzbrasse fast gleicherweise an. In Schnittpräparaten sind die elastischen Elemente in der Arterienadventitia des ersteren Fisches beträchtlich dicker und sehr stark geschlängelt. Die Muskelfasern sind in der Arterienmedia des Knorpelfisches etwas besser entwickelt als in der des Knochenfisches, dagegen finden sich die Kollagenfasern in der Adventitia des letzteren weitaus reichlicher.
3. Die elastischen Elemente der Aorta ventralis der Schwarzbrasse sind zierlich wabig strukturiert.

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No mentionable difference is observable between a 10th month human fetus and a human adult, in respect of the histology of the caruncula lacrimalis and the plica semidunaris.
The caruncula lacrimalis contains, beside numerous sebaceous glands and downed hair-follicles, in some cases MOLL's glands, accessory tear glands and small MEIBOM's glands, in its leep layer.
The superficial layer of the caruncle is made of mucous membrane of the same structure as that of the conjunctiva palpebralis adjacent to it. The epithelium is of staratified cylindrical type containing mucous cells throughout, even on the summit of the caruncle, CONTINO et al.'s statement notwithstanding, and the propria under it is composed of connective tissue full of fibrocytes in human fetus but of a reticular tissue rich in lymphocytes in adults.
From the above finding and in consideration of the absence of hair-follicles on the inner ridge of the lid-margin, the coruncula lacrimalis is not originated in the inner ridge of the lid-margin, as CONTINO has asserted, but it appears that the superficial layer of the caruncle is of the same mucous membrane as that of the conjunctiva palpebralis in origin and its deep layer is formed by subsidence of a part of the eyelid skin minus its epidermis and the papillary layer of its corium.
The mucous membrane of the plica semilunaris is of the same nature as that of the conjunctiva palpebralis and the caruncula lacrimalis, except that its propria of loose connective tissue contains far fewer colonies of lymphocytes than in the latter. On the summit of this plica or in the vicinity stand out some mucous folds containing propria of compact connective tissue rich in fibrocytes and very rich in blood vessels.
The part of the conjunctiva palpebralis adjacent to the caruncula lacrimalis is poorer in sensory innervation than its more lateral part (SETO). Accordingly, the mucous membrane of the caruncle forming an extention of this conjunctival part contains as few sensory fibres and unbranched or simple branched terminations fromed subepithelially by them as the latter. Of course, neither intraepithelial fibres nor glomerular end-bodies could be found herein.
Since in the deep layer of the caruncle can be found hair-follicles provided with sebaceous glands and downs, the nerve supply in this part is similar to that in common haired skin, but in quantity, the sensory fibres are much smaller than in other parts. These few sensory fibres run in hair-nerve bundles in company with vegetative fibres and most of them come into the SETO's so-called hair-nerve shields in the hair-follicle necks, to end in very simple plexus-like terminations. The terminal mode here is perhaps the simplest of all parts of haired skin. A small part of the sensory fibres depart from the hair-nerve bundles to run up along the sebaceous glands into the mucous membrane, to end there in the above-described simplest terminations.
Sensory fibres are found running into the mucous membrane of the plica semilunalis too, in a number somewhat larger than those supplied to the mucous membrane of the caruncula lacrimalis. But the number, after all, is severely limited by the paucity of sensory nerve elements common to all parts of the conjunctiva palperbralis. Their terminations are also very simply constructed, in no case going beyond the simplest unbranched type ending subepithelially, except in the special mucous folds containing compact connective tissue rich in blood vessels, where a large number of vegetative fibres and a small number of sensory fibres participate in forming relatively complex nerve plexus, of which the sensory fibres come out to form beside unbranched terminations also simple branched terminations. In the plica semilunaris were found no intraepithelial fibres, either,
The vegetative fibres, both in the caruncula lacrimalis and the plica semilunaris

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The canine eyelid shows little essential difference in histology from that of man, but it shows sundry features in the relative development and arrangement of the component parts specific to dog, which stand in close relation to the innervation, especially sensory innervation of the parts.
The tarsus is powerfully formed and contains well developed MEIBOM's glands. The conjunctiva palpebralis is composed of only a very poorly developed propria and a thin uncornified stratified flat epithelium in the area where it touches the tarsus, but in the deeper part, the epithelium changes into a cylindrical one, the propria becomes thicker and the so-called papillary bodies are formed.
The lidmargin is covered by a mucous membrane, of which the epithelium is a stratified flat one of considerable thickness and provided with a horn-plate. But, the development of the propria and the papillae into the epithelium is far worse developed than in man.
The outer edge of the lidmargin is covered by a haired skin, on which grow eyelashes in 2-3 rows, of which the hair-follicles and the sebaceous glands belonging thereto are considerably well developed. This part as well as the cutaneous part of the eyelid have a thin epidermis, under which the stratum papillare is very poor in development, being nearly altogether absent in some places. In this palpebral skin, we must specially mention that instead of the meagre downs on human eyelids hairs with follicles only somewhat inferior to the eyelashes in development are rather densely growing, and that peculiarly shaped epidermal swellings are often formed in the epidermis. These swellings are of deep interest as no such formation has ever been found in man and seem to be sensory receptors of a specific kind.
The sensory innervation of the conjunctiva palpebralis is much poorer than in man, especially so in the area touching the inside of the tarsus, owing to the extremely poor development of the propria. Namely, only a very small number of sensory fibres run into it and their terminations are limited to the simplest unbranched type, such glomerular terminations as found in man being never found. No intraepithelial fibres have been demonstrated here either. The propria of the conjunctiva after parting from the tarsus and nearing the fornix, however, becomes better developed and the sensory fibres coming into it somewhat increase in number. These fibres always end subepithelially in simple branched terminations.
The canine tarsus contains sensory fibres though smaller in quantity than in the human tarsus, and their terminations formed therein are also simpler than in man, usually consisting only of simple branched terminations which are mostly formed in the marginal parts of the tarsus, that is, adjacent to the conjunctiva palpebralis and the lidmargin. The fibres resemble those in the human tarsus only in that they consist in thick fibres frequently changing their size and that their terminal fibres end sharply or bluntly. Some of these terminations are often found extending from the tarsus into the propria of the palpebralis and the lidmargin.
The propria of the lidmargin is very poor in development, and accordingly the sensory fibres and their terminations in it are also much inferior in development than those in man. So nothing comparable to the very peculiar complex glomerular or loop-like terminations as found in man was ever found in dog, only a few straggling sensory fibres being observed ending subepithelially in unbranched or simple branched terminations.
The outer edge of the lidmargin and the skin part of the lid are covered by a common haired skin, and most of the rather numerous sensory fibres coming into there end in the SETO's so-called hair-nerve shields or tubes in the specific tissue hair-follicle necks as sensory hair-nerve fibres, only a small part ending in the stratum papillare.

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The innervation of the testicle and the caput epididymidis originate in the plexus spermaticus and that of the corpus and the cauda epididymidis in the plexus deferentialis. Between the two kinds of plexus only slight anastomosis is to be observed.
The plexus deferentialis is formed in the vasa deferentialis, spreads to the cauda epididymidis and thence into the corpus epididymidis and turns into the plexus ductus epididymidis. The plexus spermaticus runs through the plexus pampiniformis and thence spreads into the caput epididymis and the testicle. In the former part it forms the plexus ductuli efferentis, but in the latter, it passes first over into the plexus mediastinalis testis and the largest part of its nerve elements runs thence into the tunica vasculosa and finally spread out into the interstitial connective tissue through the septula testis. A small part of the nerve fibres of the plexus mediastinalis testis, however, run through the rete testis into the parenchyma testis.
The plexus ductus epididymidis is very well developed already in the later fetal stage and comes into frequent anastomosis with the perivascular plexus running along the blood vessels. The vegetative fibres always develop into preterminal fibres and thence into STÖHR's terminal reticula, which come into control by contact over the smooth muscle cells. The development of the vegetative fibres is particularly powerful in the cauda epididymidis where the muscle layer of the ductus is well developed.
The plexus ductuli efferentis is far poorer in development than the plexus ductus epididymidis, due to the poor development of the muscle fibres in this part. The vegetative fibres here too end in STÖHR's terminal reticula, which run as far as into the membrana propria but not further in the epithelial cells of the ductuli. STÖHR's terminal reticula are formed in the interstitial connective tissue of the testicle too, but in the fetal stage, they are far poorer in development than in human adults. The terminal reticula here stand in control by contact over the LEYDIG's cells.
A small number of sensory fibres are found in the plexus spermaticus. These probably originate in the branches of the nn. sacrales running into the plexus hypogastricus.
The sensory terminations found in the testicle and the epididymis, being originated in the sensory fibres running in the plexus spermaticus, are present in the testicle and the caput epididymidis, but scarcely in the corpus and the cauda epididymidis.
The sensory fibres running toward the mediastinum testis seem to be somewhat more numerous than those directed toward the caput epididymidis. The former part from the vegetative fibres upon reaching the rete testis, run through the connective tissue lining the rete or between its ducts and end in unbranched and simple branched terminations. Their terminal fibres show frequent change in size and usually end in sharp points. Often they penetrate into the one-rowed epithelium of the rete and end as intraepithelial fibres.
The above findings are not much different from those obtained in adult human specimens by YAMASHITA. Thus, the sensory terminations in these parts seem to reach nearly complete formation in the fetal stage. Not rarely are found sensory fibres running further beyond the rete testis into the tunica albuginea and forming their terminations there. In the parenchyma testis, however, no sensory termination has been found.
In the corpus and the cauda epididymidis no sensory termination has been adequately ascertained, but in the caput epididymidis may be seen some unbranched and simple branched terminations similar to those found in the rete located in the interstitial connective tissue of the ductuli efferentes. But here no intraepithelial fibres as found in the rete testis are observed.

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