168 SUMMARY OF CURRENT RESEARCHES RELATING TO 



cells (Keimzellen of His). The latter divide by karyokinesis, and give 

 origin to other cells which are transformed into neuroblasts. 



With this conclusion Dr. Giglio-Tos cannot agree. In early stages 

 in man only one kind of cell — epithelial — is distinguishable. These 

 are capable of dividing by karyokinesis, and in so doing they lose 

 their elongated form and appear like the Keimzellen of His. 



Efferent Neurons in Electric Lobes of Torpedo occidentalis. * — 

 Shinkishi Hatai finds that these present a fibrillar appearance of the 

 ground -substance, but that this is due to an alteration in the shape of 

 the meshes of the reticulum, and, therefore, cannot be compared with 

 the fibrils described by Bethe, Apathy, and others. The meshes of the 

 reticulum, which the author regards as primitive, are altered by the 

 growth of the cell-body where the processes, both axone and dendrite, 

 arise. In these branches they become extremely elongated. In con- 

 firmation, the author describes, in the spinal ganglion-cells of the white 

 rat, the gradations from the primitive shape of the meshes to the altered 

 form which appears fibrillar. 



Nerve-Endings in Taste Menisci.f — Dr. Eugen Botezat has studied 

 these end-organs in various mammals, and finds that they are to be 

 regarded as telodendrites, which surround epithelial cells from one, 

 several, or all sides, and convert the cells into taste-cells. The menisci 

 are connected with each other by means of primitive fibres, and the 

 telodendrites often give off fine fibrils, which in all probability have 

 intracellular terminations. 



Nerve-Endings in Peritoneum of Mammals.^ — Dr. D. A. Timcfejew 

 finds that the peritoneum of mammals is usually abundantly furnished 

 with sensory end-organs. In the parietal peritoneum he finds the fol- 

 lowing types : — (1) In the sub-serosa numerous free end-organs in the 

 form of end-tufts ; (2) a smaller number of organs of peculiar shape 

 which may be called " denticulated end-plates " ; (3) in the deeper 

 layers of the sub-serosa cylindrical end-bulbs. In addition, the serous 

 layer contains a plexus of non-medullated fibres which sends out fine 

 branched non-medullated fibrils. The diaphragm contains also the 

 three types of end-organs mentioned above. In the centrum tendineum 

 there are flattened or leaf-like end-organs, and also cylindrical end- 

 bulbs. In the muscular regions there are motor end-organs of the usual 

 type. All the forms of sensory end-organs mentioned above appear to 

 arise from medullated fibres, and in certain cases, e.g. that of the cylin- 

 drical end-bulbs of the diaphragm, the author was able to prove that 

 they originate from the phrenic nerve. He therefore believes that this 

 nerve is to be regarded not only as the motor nerve of the diaphragm, 

 but also as the sensory. 



Innervation of Supra-orbital Canal in Chimaera monstrosa. § — 

 11. H. Burne comments on Cole's discovery that two organs in the middle 

 of the supra-orbital canal in this hsh are innervated by twigs from the 

 ramus ophthalmicus profundus of the Vth cranial nerve —apparently 

 the only genuine case of connection between the nerves of the lateral 



* Journ. Cincinnati Soo. Nat. Hist., xx. (1901) pp. 1-12 (1 pi.), 



t Ztitschr. wiss. Zool., lxx. (1901) pp. 559-66 (1 pi.). 



t Arch. Mikr. Anat., lix. (1902) pp. 629-46 (1 pi.). 



§ Proc. Zool. Soc. London, 1901, pp. 184-7 (1 fig.). 



