Miscellaitequs. 5u9 



met with ; and it is in this state e8i)ecially that the physician should 

 bo able to reco^^nizo them. At this time they are O-li'-S millim. in 

 Icnf^th and i)-0'22 millim. in breadth. The oesophagus shows its 

 characteristic form verj- well, reseml)linp; a pestle with two heads, 

 one cylindrical, the other 8j»heric;il. The intestine contains fatty 

 {j;lol)ules, no doubt derived from the milk which constitutes the 

 patient's diet. The uterus only api)ears in the form of a vesicle on 

 the right side of the animal ; the vulva is not yet open. 



Five days suffice for the JiJialx/itis steirorulis to attain its com- 

 l)lete development under favourable circumstances ; hence its ex- 

 treme abundance in the intestines of the patients. 



In tine, this Xematode, very nearly allied to Rhahditls tcrrkola, 

 Duj., so well described by M. Peres, differs from the latter in its con- 

 stantly smaller size, but especially in the form of the penial appa- 

 ratus, whicli is moreover destitute of cirri and of the caudal hood. 



Dr. iS'ormand has met with this parasite in the stomach, in the 

 whole of the intestine, in the pancreatic duct, the gall-duct, the 

 hepatic ducts, and on the walls of the gall-bladder. — Conqites 

 licndits, October D, 1870, p. 6ii4. 



On the Intim'iie Phenomena of Cell -Division. By M. H. FoL. 



In my memoir on the Geryonidae I gave the first exact description 

 of these phenomena, which previously had not been understood either 

 by botanists or zoologists. All the principal points in those pro- 

 cesses, such as have been since made known in more detail, were 

 contained in the above-mentioned description. My observations 

 were soon confirmed by the independent works, posterior to mine, 

 of MM. Flemming and Biitschli ; and my theoretical ideas have 

 received valuable support from M. Flemming and especially from 

 M. Ijobretzky. I have now to communicate the results of the in- 

 vestigations I have just made upon segmentation in the Hcteropoda, 

 the Echini, and in ^(trjitta, which appear to me fitted to lead to the 

 modification of the ideas accepted by most recent authors. 



The centres of attracrion appear, before each segmentation, at the 

 two opposite poles of the nucleus, which is still absolutely intact, 

 and seem to be a local fusion of the substance of the nucleus with 

 the vitelline protoplasm, or perhaps an irruption of the protoj^lasm 

 into the more fluid interior of the nucleus. To these two small 

 aggregations of sarcode, rays of sircode immediately run, some of 

 them extending in the inferior of the nucleus from one centie of 

 attraction to the other, wliilst the other rays diverge in the vitellus. 

 I first described this formation of rays in Pteropoda ; and M. lio- 

 bretzky has arrived independently at perfectly concordant residt.*!, 

 in his remarkable memoir on the embryogcny of the Gasteropoda. 

 M. Ihitschli ascribes especial importance to the intranuclear fila- 

 ments, to which he gives the name of fibres ; whilst the filaments 

 which lose themselves in the vitellus arc regarded by him merely as 

 striic. This distinction is founded especially on the difl'erint aspect 

 of these two kinds of filaments, a ditterence which is quite naturally 

 exi)lained if we consider that the intranuclear filaments are im- 

 mei-sed in a nearly fluid medium mucli less refractive than the prolo- 



Anii.d: MiKj. N. Ilist. Ser. 4. I'c/. xviii. 35 



