24 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Wagner's " bouquets." This indeed is the interest of the observation, — 

 that it describes a state intermediate between that which usually occurs 

 and that in the torpedo. 



Structure of Stratified Pavement Epithelium.* — Sig. C. Foa has 

 studied this in embryos of ox. He finds that between the cells there 

 run closed chambers, like prisms, with polygonal section ; in the older 

 foetus the limiting lateral lamime coalesce, gradually thin off, and the 

 lines of their intersection thicken, leaving eventually bridge-like threads 

 between which there are spaces in which the nutritive fluid circulates. 



Fat in Cartilage. f — Dr. C. Sacerdotti concludes, from detailed 

 experiments, that the presence of fat in cartilage-cells is normal and 

 constant. It increases pari passu with the functional development of 

 the elements ; it does not diminish during inanition, but only when the 

 nutrition of the cell is profoundly altered. 



Absorptive Affinities of Vascular Endothelium.! — Henri Stassano 

 has made experiments which go to show that the vascular endothelium 

 has a particular affinity for mercury, thus explaining the predominance 

 of this toxic in the more vascular organs. The same is true also in 

 regard to strychnine and curari ; and the general result of the investiga- 

 tion is to show the importance of the endothelial cells in absorption as 

 well as in arrest. 



Cell-changes during Digestion. § — Prof. E. Wace Carlier has studied 

 this subject in the stomach of the newt. He finds that in the cells 

 prozymogen is produced by the nuclei at the same time that the zymogen 

 already formed is being secreted by the cell in the form of zymin. The 

 nucleoli consist entirely of effete matter produced during nuclear acti- 

 vity, and ultimately passed out into the cytoplasm. The nucleoli do not 

 become converted into zymogen granules. Nuclear exhaustion is due 

 to the manufacture of prozymogen, which arises from the nuclear 

 chromatin. The chromatin is renewed by the entrance into the nuclear 

 juice of a coagulable substance, which probably includes a proteid. Both 

 chromatin and zymogen contain the same nuclein radicle, but differ in 

 the amount of linked albumin. Parazymogen is chromatin less some 

 of its albumin ; it takes up some albumin from the cytoplasm, and 

 becomes converted into zymogen. The albumin separated from the 

 chromatin during the formation of parazymogen goes to form the 

 nucleolus. 



Dermis and Epidermis. || — Dr. Ed. Eetterer has always opposed the 

 current views as to the relation of these two structures. He believes 

 that the facts both of histogenesis and of transplantation experiments 

 show that the epidermis itself, or the subjacent epithelial membrane, 

 gives rise to the connective-tissue of both the adult and embryonic 

 dermis. In other words, it is incorrect to say that the epidermis forms 

 a permanently distinct membrane, growing only from within outwards. 

 Till recently his observations have received no support or confirmation 



* Atti E. Accad. Sci. Torino, xxxiv. (1899) pp. 1004-12 (1 pi.). 



f Tom. cit., pp. 984-1003 (1 pi.). 



I Comptes Rendus, cxxix. (1899) pp. 648-51. 



§ La Cellule, xvi. (1899) pp. 405-64 (3 pis.). 



|| Journ. Anat. et Physiol, xxxv. (1899) pp. 675-6. 



