222 ANIMAL PARASITES AND MESSMATES. 



It was with these cysticerci that I made experiments 

 on four dogs, which I took with me to Paris, in order to 

 convince those who could not believe in the migration 

 of parasites. It was this species that I gave also to the 

 dogs which served as a demonstration at Paris at the 

 course of lectures given by Mons. Lacaze Duthiers. 



Some years ago, while making a post-mortem ex- 

 amination, at the Museum of Paris, of some young dogs 

 which I had previously infected with Tmnia serrata at 

 Louvain, there were found by the side of these some Tdeniae 

 cucumerinse. These dogs had taken nothing but milk 

 and cysticerci ! Whence came these Teenise cucumerinw? 

 1 knew not, and I frankly owned it to the members of 

 the Commission who proposed the question to me. This 

 however did not prevent my being greatly puzzled with 

 the presence of this worm of whose origin I had no idea. 

 Now we know whence they came. An acaris, the Tri- 

 chodectes, lives in the hair of young dogs and harbours 

 the scolex of this cestode. The dog, by licking its own 

 hair, grows infested, like the horse, which in a similar 

 manner introduces the gad-fly, and although it has taken 

 no other nourishment, harbours its own epizoaria. 



The name of Cysticercus tenuicollis has been given to 

 a vesicular worm which inhabits the peritoneum of the 

 ox, the goat, the sheep, &c., and which turns to a taenia 

 in the digestive tube of the dog. Mons. Baillet has made 

 the principal experiments on this transmigration. The 

 itinerary of another cestode worm, the Coenurus of the 

 sheep, is to pass through the sheep in order to reach the 

 wolf or the dog. This worm has only lately been recog- 

 nized in its tsenoid form ; it has, on the contrary, been 

 long known under the name of Coenurus cerehralis ; this 



