ZOOLOGY AXD BOTANY, MICROSCOPY, ETC. 39 



of the beginning of the epididymis — the vasa efferentia and coni 

 vasculosi — consist of ciliated cells, which from time to time secrete 

 and lose their ciliary apparatus, regaining it after the secretory process 

 is over. These cells contain " diplosomes" which are quite distinct 

 from the centrosomes visible at the poles of the achromatin-spindle of 

 dividing cells. The secretory activity leads to the gradual disintegration 

 of the cells, which are then replaced. Many other histological details 

 are communicated ; we have simply noted the salient points. 



Peculiar Structures in Hepatic Cells.* — Eugenie Koiransky gives 

 a detailed account of peculiar rod-like or strand-like structures observed 

 within the cells of the liver in frog, newt, and salamander. They are 

 often substantial, and proceed from the nucleus towards the periphery 

 of the cell, which they often reach. It is maintained that there is in 

 secretion a shunting and migration of chromophilous substance towards 

 the capillaries along protoplasmic strands, controlled by the kinetic 

 potencies of the protoplasm, and that this is followed by a granular 

 disruption, a chemical change, and a final solution of the substance in 

 the vicinity of the capillaries. 



Position of Glycogen in Liver Cells.f — 0. Petersen points out 

 that great care needs to be exercised in explaining alcohol-fixed pre- 

 parations with reference to the position of glycogen within the cells. 

 For this the method of freezing sections is more reliable. In cases of 

 lateral penetration of alcohol the glycogen lies on the same side of all 

 the cells, viz. remote from the side of penetration, as if pushed in front 

 of the alcohol. 



Islets of Langerhans in Teleostei. :|: — J. Rennie has investigated 

 the pancreas of a large number of bony fishes, and finds that these 

 islets are a common character in the group. In a number of species 

 there is an encapsuled islet ("principal islet") of relatively large size, 

 of constant occurrence, and with definite relations, whose association 

 with the pancreas is frequently extremely slight. In some forms it was 

 the only body of this nature found. The smaller islets which do not 

 appear to be constant in number, probably originated as accessory 

 bodies, but are now established as definite organs. It is concluded that 

 these islets are blood glands, whose relation with the pancreas is 

 secondary. This has been brought about in Teleostei mainly by the 

 tendency of the diffuse pancreas to envelop or invade other tissues. 

 In the case of these so-called islets in the compact pancreas of Teleostei, 

 and also of higher animals, the closer relation is due to the common 

 embryonic origin of the two tissues. The primitive condition is that 

 ' exhibited by Teleostei with diffuse pancreas, where the islets are both 

 morphologically and functionally separate. 



Granular Cells in Epidermis of AmmocoBtes.§ — N. Loewenthal 

 makes some notes on these cells. He describes the thread-like continua- 



* Anat. Anzeig., xxiv. (1904) pp. 435-56 (6 figs.). 



+ Op. cit., xxiv. (1904) pp. 72-5. 



t Quart. Journ. Mior. Sci.,xlviii. (1901) pp. 379-40;") (3 pis.). 



§ Anat. Anzeig., xxv. (1904) pp. 81-94. 



