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Volume 52 (1950)
- Issue 3-4 Pages 207-
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Volume 52, Issue 3-4
Displaying 1-26 of 26 articles from this issue
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Koiti Motokawa1950 Volume 52 Issue 3-4 Pages 207-212
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe effect of color mixing on the retinal color processes was studied. In the first place, the excitability curves for two monochromatic lights were determined separately, and then the summation curve for the mixture of the two colored lights. From these experiments it was found that the law of additive summation which holds for the usual color mixing experiments does not apply to the physiological effects caused by lights in the retina. The summation curves were found a little higher than the envelope of the single curves obtained in the separate application of the colors, but the shape of the curve was very similar to that of the envelope.
Binocular mixing of colors had no influence' upon the excitability curve; From the eye illuminated by red light was obtained an excitability curve which could not be distinguished from the excitability curve for red light, by whatever color the other eye might be illuminated simultaneously.View full abstractDownload PDF (351K) -
Koiti Motokawa1950 Volume 52 Issue 3-4 Pages 213-221
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSInfluence of various colored lights upon the excitability curve for white light was investigated, and it was found that the excitability curve suffered a considerable deformation when the colored light was started immediately after the end of the pre-illuminating white light and continued until the test of electrical excitability was over. However, no such effect could be seen when the colored light was removed prior to or during the pre-illumination.
It was further elucidated that the deformation was due to selective inhibition. For example, green light inhibits chiefly the G process so tha_??_ the excitability curve for white light obtained under the inhibitory action of green light resembles that of the green-blind in whom the G process is absent. In general, colored light can inhibit the same process as it is able to elicit when it is used as the pre-illuminating light. For instance, blue light can elicit the B process, and is almost ineffective upon the other processes. Therefore blue light inhibits selectively the B process.
By taking advantage of selective inhibition the yellow process at the fovea and that outside the fovea were analysed, and it was elucidated that the yellow process at the fovea is composed of two processes R and G, whereas. the yellow process outside the fovea is an undividable single process.View full abstractDownload PDF (548K) -
Masabumi Yamasaki1950 Volume 52 Issue 3-4 Pages 222
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
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Kituya Iwama, Tokumoto Shinjo1950 Volume 52 Issue 3-4 Pages 223-229
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe methods and apparatus for leading off action currents from the human parotid gland and for recording velocity of salivary secretion were described in detail.
1) On the opening of the Stensen's duct we fixed a Krasnogorski's. suction capsule in which a small silver electrode was placed. A diffuse electrode of silver was placed on the skin of the parotid region. In response to a gustatory stimulus a galvanometer which was connected with the pair of electrodes showed a marked deflection accompanying an increased salivary secretion. It was found that the elicited action current consisted of a slow potential change and rapid potential waves superimposed upon it.
2) With a simple apparatus, secretion velocity was recorded photo-graphically. It was shown that the time course of the velocity was closely similar to that of the action current.View full abstractDownload PDF (430K) -
Toshio Kurokawa, Tatsuo Saito, Hajime Amakasu1950 Volume 52 Issue 3-4 Pages 230
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
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Tokumoto Shinjo1950 Volume 52 Issue 3-4 Pages 231-240
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSUsing Krasnogorski's capsule, secretion of the human parotid was studied. The action current accompanying secretion was led off to a mirror galvanometer through a pair of silver electrodes, one of which was placed within the capsule, and the other on the skin over the parotid, and recorded photographically.
1. The action current consisted of two components; the slower com-ponent appeared after a latency of 0.2 to 4 seconds, and lasted for 1 to 5 minutes, the direction of the current being from cheek to mouth in the external circuit. The more rapid component consisted of small waves with a period of about 5 seconds, and appeared superimposed upon the slower component.
2. Acid and salt gave rise to action currents of similar type, consist-ing of a large deflection with a train of small waves superimposed. Action currents caused by sugar and quinine were also similar to each other. They were much smaller in amplitude, shorter in duration and scant of small waves.
3. The relation between the amplitude of action currents and the number of drops of saliva secreted during 30 seconds after the onset of a stimulus was studied, and it was found that they are related linearly to each other at lower concentrations of test solutions, but that the amplitude in-creased much less than in proportion to the number of drops at higher con-centration.
4. The latent period of action currents depended little on the kind of taste substances, but greatly on concentration.View full abstractDownload PDF (513K) -
Tokumoto Shinjo1950 Volume 52 Issue 3-4 Pages 241-248
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSFacilitation and inhibition in taste sense were studied objectively, taking the latent period of salivary secretion or of action currents of the parotid as the index.
1. Facilitation was shown by mixing acid of fixed concentration with salt of varying concentration.
2. The latency decreased with increasing concentration of salt. A similar relation was found in mixing quinine (constant) with sugar (varia-ble).
3. Inhibition was found in mixing acid (constant) with sugar (varia-ble); The latency increased as the concentration of sugar in the mixture was raised.
4. In the combination of salt (constant) and sugar (variable) the longest latency was obtained at about 15% of sugar. Similarly there was a maximum of latency at a certain concentration of quinine mixed with a constant amount of NaCl.
5. There was a minimum of latency at a certain concentration of quinine mixed with a constant amount of acid.
6. The effect of rinsing with various taste solutions upon the latency of secretion or that of action current caused by 2% NaCl solution was studied, and it was found that rinsing acts facilitating upon salivary secre-tion at lower concentrations of a rinsing solution, but inhibitory at higher ones.
7. The longest latency was obtained at 35°C in the experiments with our taste qualities of varying temperature.View full abstractDownload PDF (384K) -
CXXIX. Chondrosin. Seventh ReportTuneo Nagaoka1950 Volume 52 Issue 3-4 Pages 249-250
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
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172nd Report of the Peroxidase Reaction. (119th Human Milk Study.)Akira Sato, Tsuneo Arakawa1950 Volume 52 Issue 3-4 Pages 251-254
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
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Hyoe Okabe1950 Volume 52 Issue 3-4 Pages 255-264
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESS1) A strain of Gram positive, spore forming bacilli was isolated selectively inhibitory for Gram positive bacteria.
2) This strain seemed to belong to the Bacillus subtilis group according to the morphological and biochemical properties.
3) The colony on the nutrient agar plate was S type, unlike the other a_ ntogonistic strain already reported.
4) The medium for the production of the antibiotic consisted of meat extract 10g, peptone 10g, KH2PO4 1g, Na2HPO4 12H2O 0.25g, NaCl 5g, conc. “Dokudami” extract 2cc and tap water 1000cc
5) The 24 hours culture of this strain in the medium at 30°C showed 1:640 dilution titre for “Terashima” strain.
6) The active substance was found to be stable toward the heating at weakly acidic pH, toward the preservation for 6 months and toward the oxidation by aeration.
7) The concentrated centrifuged supernatant was bactericidal.
8) This substance was soluble in water and butanol containing water and insoluble in alcohol, ether, acetone, methanol and butyl acetate at pH 7.0.
9) This substance could be extracted by shaking with butanol at pH 8.0-9.0. By this property its purification was possible to a certain extent.
10) This antibiotic substance was active only for Gram positive bacteria. The dried powder showed 1: 4, 000, 000 dilution titre for Sta-phylocous aureus (Terashima strain.)
11) Hemolytic activities were negative in a dilution of 1: 1000 of culture filtrate.
12) The M. L. D. of this substance was proved to be larger than 1000 mg per Kg of body weight of mice. The substance, therefore, seemed to be applicable for chemothrapeutic use.View full abstractDownload PDF (486K) -
Kei-ichiro Hosisima, Hyoe Okabe1950 Volume 52 Issue 3-4 Pages 265-271
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESS1) A certain sort of sterol was isolated from Houttuyna cordata (Dokudami), a japanese plant drug, which had the ability to promote the production of the antibiotic substance produced by a certain strain of Gram positive, spore forming bacilli.
2) It was proved, that the sterol isolated from the plant closely resembled sitosterol from the chemical and physical points of view.
3) There was a optimal concentration of this sterol to promote the production of the antibiotic.
4) It was shown that Phenantrene, cholesterol and other similar com-pounds had almost similar activities.View full abstractDownload PDF (326K) -
Keiichiro Hosisima1950 Volume 52 Issue 3-4 Pages 273-282
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThere were two substances isolated from the culture filtrate of this mould, one had a “fumigatin” (3 hydroxy-4 methoxy-2:5-toluquinone.)17) -like activity against microorganisms, and the other was identical with spinulosin (3:6 dihydroxy-4 methoxy-2:5-toluquinone.)
According to Oxford, 3) fumigatin was inhibitory toward Staphylococcus aureus and cholera vibrio at 1:30, 000 to 1:50, 000 dilutions respectively, so the antibiotic substance of this mould was about 30 times stronger than fumigatin. Fumigatin melted at 118°C and this substance at 184°C-185°C. Fumigatin could be sublimated in vacuo, while this substance could not be, and in other chemical properties the substance was shown to be definitely different from fumigatin.
Oxford3) also studied on the antibacterial activities of several kinds of toluquinone derivatives, and found that 3:6-dihydro-4-methoxy-2:5-toluquinone and 3-hydro-4:6-dimethoxy-2:5-toluquinone, which were synthesized by them, were far more active aginet Staphylococcus aureus than fumigatin.
Regarding with antibacterial powers, the substance isolated would be closely resembling to these substances.
Raistrick8) said that the morphological and physiological classifica-tion of the moulds was closely paralleled to the biochemical properties of the metabolic products of the moulds. In the former part of this work it was mentioned that this mould was closely related to Penicillium spinulosum which produced spinulosin in its culture media and the identity of the pigment which was produced by this mould with spinulosin confirmed the opinion.
On the other hand Raistrick and others18) separated spinulosin from the metabolic solution of Aspergillusfumigatus Fresenius, which on Rhaulin-Thom's media produced fumigatin.17) On the contrary it was a very in-teresting fact that this mould, being closely related to Penicillium spinulosum Thom, produced a substance which showed fumigatin like activities to-ward certain microorganisms.View full abstractDownload PDF (553K) -
II. An Acetic Acid-Hydrochloric Acid Reaction of Proteins. First ReportNoboru Hiyama1950 Volume 52 Issue 3-4 Pages 283-288
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
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I. On the Antitoxic Function in Healthy Med and Liver PatientsKazuichi Tsunoda1950 Volume 52 Issue 3-4 Pages 289-298
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
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II. On the Antitoxic Function of Potors and Habitual DrinkersKazuichi Tsunoda1950 Volume 52 Issue 3-4 Pages 299-305
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe examination of antitoxic function of the liver was applied to groups of habitual drinkers of spirits and some drinkers resistant to much wine, by means of santonin acid sodium charge test.
a) Examinations were performed depending on 3 standpoints; i. e. palpability of the liver, positivity of urobilin and urobilinogen bodies and Takada's reaction. Poters belonging to the 1st group, who were positive in one or more among the three, were also remarkably positive in this examination.
b) In the poters belonging to the 2nd group who revealed no notice-able finding in the above stated examination nor any sick condition, there was recognized no hepatic obstruction.
c) Livers of poters who are resistant to much quantity of spirits are considered to possess such antitoxic function as is superior to that of normal men.View full abstractDownload PDF (377K) -
III. On the Antitoxic Function of Survivers of Methyl-alcoholKazuichi Tsunoda1950 Volume 52 Issue 3-4 Pages 307-310
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe antitoxic function of the liver is examined on 15 methyl-alcohol survivers by the use of santonin acid sodium charge, in such term as in-dicates the depression of the influence of the intoxication. And it was revealed by the result that they had no noticeable hepatic obstruction, their antitoxic function being equal or rather superior to that of normal man. It is thought, therefore, that the mortal cases of methyl-alcohol patients were mostly caused by the inactivity of the antitoxic function of their livers.
Considering the stated 2nd report and this one, I take it to be a mat-ter of great significance to apply the examination of latent disturbance of hepatic function to apparently healthy persons, and it will contribute much to the diagnosis of the health.View full abstractDownload PDF (239K) -
Makoto Hayashi1950 Volume 52 Issue 3-4 Pages 311-324
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
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Isami Watanabe1950 Volume 52 Issue 3-4 Pages 325-333
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSAs a result of the electroencephalographic observation of our fifty cases, it was recognized to be valuable in the localization of superficial tumors of the convexity of the brain. In evaluating the EEG of the deeply underlying tumors, it should be emphasized that there is a near local and a far local electroencephalographic change. Therefore one should always endeavour to understand the abnormal waves recorded in EEG, with caution.View full abstractDownload PDF (462K) -
Saburo Takita1950 Volume 52 Issue 3-4 Pages 335-340
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSContrary to some writers, the present author has never come tb see the existence of epinephrine in the general blood of rabbits, poisoned by the morphine. Both the rabbit intestine segment method and the frog legs vessels method were employed. Exactly said that the epinephrine does not exist in the peripheral blood beyond the limits determinable by means of both the methods.
The failure of the previous writers might be explained probably in this way that they did not pay any attention upon the fluctuation of sen-sibility of the vessel perfusion method against epinephrine or adrenaline in the course of experiment. The second writer carried on his experiment on the animal while it was near moribund, or very weakly.View full abstractDownload PDF (305K) -
Koiti Motokawa, Kiitiro Suzuki1950 Volume 52 Issue 3-4 Pages 341-348
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe supernormal electrical excitability of the eye following an pre-illumination is reduced or abolished by the second light applied prior to the test of electrical excitability, and this phenomenon is called retinal in-hibition.
1. Retinal inhibition must be an physiological event occurring at the retina because the modifying light applied to the contralateral eye which has not been pre-illuminated, has only a slight inhibitory action upon the retinal process occurring in the ipsilateral eye, compared with the same stimulus applied to the ipsilateral eye which has been pre-illuminated. The mode of action of the light applied to the contralateral eye is not selec-tive, but all the retinal processes are equally inhibited by it.
2. The degree of retinal inhibition increases linearly with the loga-rithm of the intensity of the modifying light within the middle range of intensities.
3. Retinal inhibition depends also upon the intensity of the pre-illu-minating light; Generally the higher the intensity the more marked the retinal inhibition. The reversal of effects or facilitation occurs when the intensity is lower than a certain definite level. Such facilitation is never found when the modifying light is applied to the contralateral eye.
4. The wave-length dependence of the inhibitory effects of spectral lights upon each retinal process is closely similar to the physiological sensa-tion curve reported by Motokawa.
5. The mechanism of retinal inhibition and facilitation is discussed.View full abstractDownload PDF (492K) -
Koiti Motokawa, Kiitiro Suzuki1950 Volume 52 Issue 3-4 Pages 349-359
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe excitability curve of the human retina suffers from a considerable deformation under the action of colored light which is presented after an pre-illuminating light has been removed. The deformation is due to the inhibitory effect of colored light upon the development of retinal processes.
1. The dependence of inhibitory effects upon the time interval be-tween a flash of inhibitory light (I) and the onset of the electrical test-sti-mulus (S) was investigated, and it was found that there exist three different optimum I-S intervals for inhibition at the fovea, and that each optimum I-S interval is characteristic of one of the three basic processes R, G and B.
2. The same relation was further corroborated by employing con-tinuous inhibitory light instead of a flash, where the time interval between the removal of inhibitory light and the onset of electrical stimulation was designated as the I-S interval.
3. Outside the fovea, there appeared four optimum I-S intervals, of which three coincided with those for the R, G and B process at the fovea, and the other was shown to be concerned with the inhibition of the Y pro-cess.
4. At the extreme periphery of the retina, there appeared another kind of optimum I-S interval. It was elucidated that this interval charac-terizes the scotopic process.
5. The physiological significance of the time constants determined in the above experiments was discussed.View full abstractDownload PDF (646K) -
Junichiro Kanno1950 Volume 52 Issue 3-4 Pages 361-371
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe whole result may be summarised as follows: Aicienyaes have the sedative and paralytic action on a tadpole and a mouse; especially a mouse is killed with a considerably large dose, displaying cramp always in the course of poisoning. It is probable that they cause the paralysis of central nervous system. Each lethal dose is 2.5 to 8.0 mg. per every gram-me of mouse's weight. It is perceived that there are remarkable differences as to the toxicity. Because in this experiment, a tadpole did not develope cramp even with a considerably large dose. In the seven days inject ex-periment, the local stimulative action ensures, and it is likely that tadpoles are killed with almost the same dose as lethal dose or the less excessive dose than lethal dose.
Oxygenation by the oxygen of an originater apparatus, which springs up out of the action of super-sonic wave for the purpose of chymificating drugs, is slight and out of question.
On the isolated toad's heart, the aldehydes increase the beat and the systole and dilatation of a heart with a small dose, but with a large dose they paralyze a heart, weaken the beat or stop it at the dilative stage. It seems that its active point is there in myocardiums. At a definite con- centration a heart becomes excited with paralytic action if washed out with fresh Ringer's solution.
As for hemolytic action, it is conspicuous at high concentrations, but not at small concentrations. The blood vessel of toad's hind leg, if al-dehydes act on it with a large dose, has the systolic effect exclusively and with a small dose they have the dilative effect to some extent, but not to any definite, remarkable extent.
On bacillus, with one exception of n-capronaldehyde, aldehydes effect the action of checking growth and the sterilization action at the concentra- tions of 0.1% to 0.01%.
H. M. Vernon has shown the relative toxicity of these aldehydes on a tortoise heart. Judging from his result, I expected that those aldehydes with which I made experiment should have considerably feeble toxicity. My result coincides with L. Lewin's conclusion that Aldehydes have a strong hypnotic action.
In short, these aldehydes have the narcotic action, though in different grades, and the hemolytic action, of which I made the experiment in a test-tube, and the action of checking the growth of bacilli and the steriliza-tion.View full abstractDownload PDF (1248K) -
Shinya Miura1950 Volume 52 Issue 3-4 Pages 373-384
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSNageotte gained success in making silver fibers artificially on a slide glass by addying a proper amount of NaCI to an albumin sol, Collagen A which he had obtained after treating tendons of a rat's tail with a dilute solution of glacial acetic acid. No cells were participant of this creation. After-experiments could confirm the result of his experiment, but the suc-cess rate was found extremely low. In my early tests when I adopted- the same method of his, it was only in one specimen out of about one hundred that I could see somewhat good result. In addition, these fibers were slenderer in shape, smaller in number and poorer in dyeing acceptability as compared with those in vivo.
Thereupon, I examined into the essential factors of the artificial forma-xion of fibers and in consequence got a strong confirmation to the under-mentioned facts.
The formation of these fibers is conditioned by the same general factors which allow the sol to change into gel when the albumin coagulation is brought about. These factors are the thickness and the pH of Collagen A, the kind and the thickness of salt that the sol is treated with, and the temperature at the time of coagulation. When experiments are carried on with these five factors in their satisfactory conditions, fibers are sure to appear on the slide-glass. And what is more, the fibers formed are abund-ant and have the perfect uniformity in their dyeing acceptability and from with those silver fibers found in an organic body (shown in the photos).
Following is an abridged description of my practical experiments. Before carrying out an experiment on a slide glass, I inquired in the neces-sary conditions of the coagulation of Collagen A in test tubes.
I pour 0.1 cc. of a salt solution of different degrees of thickness into some ten tubes respectively where 0.9cc. of Collagen A has been placed. Having been given a good deal of shaking, the fluid is kept at a certain constant temperature (20-30°C). After 10-30minutes, I examine all the tubes to find some in which a whitish turbildity is clearly visible with my naked eye. I repeat this experiment on slide glasses instead of in tubes with the same process and under the same conditions. Only this time the salt solution needs to be as thick or thicker than that used in the foregoing test in tubes. Fibers are to come out without fail. This method can, with the most successful result, be applied practically to any other salt than NaCl. Moreover, the fibers formed are splendid enough to be com-pared with those in vivo and we can produce them whenever we will.
These fibers produced in our laboratories take on a great variety of form and acceptability of dyes. But they may be classified into three major classes. The fibers of type A assume a membraneous form and are dyed well with aniline blue or acid fuchsin, but colored light black or reddish purple with silver. Those of type B form a lattice-like network and those of type C are like threads, which gather together, taking the form of a textile fabric of felt. Both the last two types are rich in argyrophilis and colored jet-black with silver. They are dyed comparatively well with aniline blue, but not so well with acid fuchsin.
As has been mentioned above, there are various forms of fibers pro- duced, but as their forming conditions are clearly known in respective cases, we can experimentally make generate whichever sort of fibers of our own free will. When we use a salt solution of coagulation value, that is, of the lowest thickness enough to make Collagen A begin to coagulate, fibers belonging to type A are the most cases, and according as the solution increases in thickness, there appear those of type B and then those of type c.View full abstractDownload PDF (2565K) -
Tatuzi Suzuki1950 Volume 52 Issue 3-4 Pages 385-393
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSEserine was given intravenously or subcutaneously in etherized dog, whose suprarenal vein blood was taken by lumbar route or by the cava-pocket method. Epinephrine in the suprarenal vein blood was estimated by means of the rabbit intestine segment method.
In the most of the experiments by the lumbar route preparation, in which the basal epinephrine secretion rate was not high, i. e. 0.01-0.03γ per kg. per minute from one gland, the rate of epinephrine secretion after eserine injection remained unaltered or accelerated. But the peak of the accelerated secretion was not high and was under 0.2γ. On the contrary, the action of eserine was enormous in the experiments of cava-pocket me-thod. In the latter cases, in which the basal secretion rate was 0.13-0.68 γ-per kg. per minute from both glands, the peak of the augmented epine-phrine secretion after eserine was 0.6-3.8γ. Further in the chronically splanchnicotomized dog non-effectiveness of eserine upon the-epinephrine secretion was observed.
The action of eserine above quoted may be explainable, if we take the idea of chemical transmission of never impulses into consideration.View full abstractDownload PDF (1178K) -
Takeshi Kurobane, Kakuzo Ishibashi1950 Volume 52 Issue 3-4 Pages 395-396
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
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Tosisada Mita, Kazuo Hironaka, Izumi Koike1950 Volume 52 Issue 3-4 Pages 397-405
Published: September 30, 1950
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESS“Empfindungszeit” (“E. Z.”) for a wide range from the center to the periphery of the retina was measured by a modified Hazelhoff's method under various states of adaptation.
(1) It was proved that our method satisfied the necessary conditions for measuring the “E. Z.” that an observer could make his gaze follow a fixation point travelling at a constant speed.
(2) The speed of the eye movement has no influence on the “E. Z.” within the range of the speed from 10° to 44° per sec. in visual angle in the horizontal direction.
(3) At a constant intensity of a light stimulus, light adaptation causes an elongation of the “E. Z.”, and the ratio of the “E. Z.'s” determined predominantly by the cone function at two different retinal parts remains constant irrespective of adaptation.
(4) Under dark adaptation, the value of the “E. Z.” at a high in-tensity of the stimulus shows two minima at the fovea and about 30° peri-phery and two maxima at about 10° parafovea and the extreme periphery, while the value of the “E. Z.” at a low intensity of the stimulus shows only a minimum at about 30° periphery.
(5) The question whether cones or rods predominate for the “E. Z.” seems to depend on the ratio of the densities of rods and cones of the retinal area stimulated. The shortest “E. Z.'s” determined by the cone function and by the rod function are obtained at the fovea and at about 30° peri-phery respectively, and the former is shorter than the latter.
We wish to thank Prof. K. Motokawa for his advice and helpfulness.View full abstractDownload PDF (523K)
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