Summary: A comparative study on inherited tooth morphology characters, in particular the incidence of Carabelli tubercles in the maxillary dentition, was conducted on standized stone casts obtained from 240 Japanese(124 males(_??_)and 116 females (_??_))and 160 Chinese (74_??_,86_??_)young adults. The following results were obtained: 1)No s ignificant differences in the incidence of Carabelli tubercles according to sex or body height were found between the two groups.2)However, significant differences in the incidence of Carabelli tubercles according to sex were found in both groups. The tubercles occurred more frequently in males.3) Significant differences between the bilateral and unilateral occurrence of Carabelli tubercles were observed in both the Japanese (p<0.05) and Chinese(p<0.01) groups; Carabelli tubercles on upper first molars were always bilateral.4) The highest incidence of Carabelli tubercles was found in individuals with a body height of 166-175 cm in both groups, and a significant difference (p<0.05)between the 156-165 cm and 166-175 cm groups was particularly evident in the Japanese adults.
The authors postulate that bilateral occurrence of Carabelli tubercles was originally an inherited character in the molar region, but that the character was inhibited during the process of evolution of the masticatory system and regression of the molar dentition.

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Summary: The effects of streptozotocin treatment on parathyroid water-clear cells in golden hamsters were investigated. In the cytoplasm of the water-clear cells, lipid droplets were increased as compared to that of the control animals. This finding suggests that treatment of streptozotocin affects functional activity in the parathyroid water-clear cells of the golden hamsters.

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Summary: Efferents from the optic tectum to the brain stem in the Japanese quail (Coturnix japonica) were studied with the anterogradely biocytin method. After injection of biocytin into the ipsilateral optic tectum, labeled terminals were seen in the rotund nucleus (Rt), neuropil part of the ventral lateral geniculate nucleus (GLnv), principal part of the dorsal lateral geniculate nucleus, lateral part of the dorsolateral thalamic nucleus, triangular nucleus (T), superficial parvocellular nucleus (SPC), pretectal nucleus, pretectal area (PA), subpretectal nucleus, central gray matter (GC), isthimo optic nucleus (ION), magnocellular and parvocellular parts of the isthimo nuclei (Imc and Ipc), semilunar nucleus (SLu), lateral and medial pontine nuclei and reticular formation (FRM) of the medulla, ipsilaterally. Labeled fibers were seen in the septomesencephalic tract nucleus, FRM, interstitio-paraetecto-subpraetectal nucleus, and the dorsal and ventral tectoreticular tracts (TRd and TRv). In the contralateral brain stem, labeled terminals were seen in the Rt, T, FRM, PA and paramedian nucleus. The contralateral terminals were remarkably fewer than those of the ipsilateral side. The present findings of the labeled terminals of the SPC and the GC at the level of the mesencephalic nucleus of the trigeminal nerve (MnT), and the topographic projection from optic tectum to the Rt in the thalamus, were original observations in the avian. The labeled terminals in the GLnv, Ipc, Imc and ION showed topographical projections from the optic tectum. Pathways to the contralateral brain stem were via the commissure posterior, ventral supraoptic decussation, and the predorsal bundle. The present results suggest that tectofugal impulses in the quail relate to various functions with special relation to the function of the GC at the level of the MnT as well as a visual function.

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Summary: The demonstration of prolactin in cestodes, Taenia solium and Taenia hydatigena, was investigated by using Immunocytochemical method. PRL immunoreactivity was widely distributed in the CNS and PNS in the worms. In the scolex PRL-IR perikarya occurred in the cerebral ganglia, around the basic area of the sucker and the rostral border region between the rostellum and the suckers with strong immunoreaction, distinctly in Taenia solium. A number of PRL-IR nerve fibres were observed in the main nerve cords, and a few fibres in the transverse nerve commissure. The holdfast musculature of the scolex was innervated by the PRL-ER fibres. A large number of PRL positive cells with processes and nerve plexuses were seen in the ootype/Mehlis' gland complex, oviduct, the duct of uterum, seminal receptacle and its associated duct, conspicuously in Taenia hydatigena. PRL-IR was evident in the wall of was efferens of testes and was deferens. A few PRL positive cells occurred in the medullary parenchyma amongst testes and sent their varicose processes to terminate to the testes. On the wall of the main excretory duct a few PRL-IR cells and fibres were seen.

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Summary: Enzyme-histochemical methods of staining for 5'-nucleotidase (5'-Nase) and alkaline phosphatase (ALPase)were successfully applied to study the distribution and architecture of lymphatic vessels and their relationships to blood vessels in the rat stomach. Extensively lymphatic capillary networks were found in the gastric wall, but there were significant differences in their extent, pattern, distribution and structure in the four different zones: esophagus-stomach (E-S), forestomach-corpus (F-C), corpus-antrum (C-A) and antrum-duodenum (A-D).5'-Nase-ALPase double staining revealed that the 5'-Nase-positive lymphatic vessels run in close proximity to ALPase-positive arteries and veins. The fine blood capillary network was located superficially to the lymphatic network within the same layer in the gastric wall. The abundant lymphatic network located in the deep lamina propria and the lamina muscularis mucosa was always closely associated with the base of the lowest gastric glands, and yet no interglandular lymphatic capillaries were encountered in the corpus or antrum. In contrast, fewer lymphatic capillaries were present in the lamina propria beneath the squamous epithelium of the forestomach. The distribution of the well-developed lymphatic networks with valve-like structures in the submucosa and subserosa exhibited typical features, i. e., the distribution was annular in the submucosa and fan-shaped in the subserosa in the antrum near the duodenum. Open junctions of lymphatic endothelial cells were seen in the deep lamina propria and submucosa. Collecting lymphatics containing valves were mainly located deep in the submucosa and subserosa. The deep lamina propria and submucosa may play a key role in lymph formation and interstitial tissue fluid homeostasis as well as in pathological processes in certain diseases. The present findings obtained by interstitially injecting ultra-fine carbon particle suspensions or Evans blue showed that a great deal of lymph drained into the lymphatics accompanying the left gastric artery. The existence of a forestomach may explain the complicated organization and constitution of lymphatic networks in the rat stomach.

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Summary: This paper discusses muscle phylogeny based on muscle innervation and defends a new concept of nervemuscle specificity. Some researchers argued strongly against this concept in the first half of this century. However, we think their arguments were partially based on insufficiently examined findings of the ramification manner of the radial nerve. We have dissected 140 limbs of 25 species in mammals and reptiles to examine the manners of ramification of nerves supplying the forearm extensors. The pattern of the radial nerve has been revealed to consist of consistent and inconsistent elements. The branches to the forearm extensors except for the supinator follow quite consistent patterns, while the branch(es) to the muscle is much less consistent. Comparing the ramification patterns of the nerves between mammals and lizards, it can be concluded that the radial nerve in mammals is formed by the phylogenetic path alteration of its partial nerve fibers from the pathway along the flexor side in lizards to the route in the extensor side.

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Summary: The tongue of Enhydra lutris (sea otter), died from brain contusion at the first day of its age, was investigated by light and scanning electron microscopy in this study. Three types of papillae (filiform, fungiform and circumvallate papillae) were present on this tongue. In our evaluation, the filiform papillae were divided into four shapes which were conical, club-shaped, large horny and triangular papillae. The different types of filiform papillae were located in different area of this tongue. The fungiform papillae were divided into two shapes, which were hemispherical or club-shaped, and were distributed among the filiform papillae on the dorsal and the margin of the tongue. These papillae had many taste buds in the epithelium of the dorsal aspect of them. The circumvallate papillae were present in a V-shaped row at the posterior part of the lingual body, and many taste buds lay in the epithelium of both the lateral walls facing the trench and dorsal aspect of the papillary body, and then the ducts of the serous glands opened into the floor of the trenches. The lingual mucosa of the interpapillae area at the pharyngeal part of the tongue contained taste buds and the ducts of the mixed glands opened there. Based on our examination, the lingual papillae of this newborn sea otter had many features which were described to be peculiar to young stage of mammals.

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