TBANSMIGRATIONS AND METAMOBPHOSES. 221 



other hooks in the form of a crown appear by the side 

 of four rounded projections, the future suckers; and, 

 sheathed in a large- vesicle full of a limpid fluid, it waits 

 patiently for the moment when it will find a place in the 

 stomach of a dog. If good fortune awaits it, it will wake 

 up, some fine day, in the stomach of the animal which 

 has eaten the rabbit, its former home, and a new life 

 will commence for it. The organs in which it was im- 

 prisoned are digested, it gets rid of all its swaddling- 

 clothes, unrolls itself, separates from the vesicle which 

 has protected it hitherto, and penetrates into the intes- 

 tine ; there, immersed in the food of its host, it grows 

 with extreme rapidity, and assumes the form of a ribbon 

 or tape. The ends of this tape are successively matured, 

 detach themselves, and become the complete worms, full 

 of eggs, which are evacuated with the feces; scarcely 

 have they made their appearance in the open air before 

 they burst and scatter their eggs. 



He whose scientific curiosity is sharpened, has only 

 to watch the dung of the dog at the moment of its 

 evacuation to distinguish on its surface worms of a 

 milky-white colour, contracting like leeches, which are 

 the true Taenia serrata in its adult state. Experiments 

 made on this species have given sanction to what I had 

 said respecting the cestodes. 



The taenia, under the name of Cysticercus cellulosus, 

 lives in the folds of the peritoneum of the rabbit and 

 the hare, and passes directly from the rabbit to the dog 

 to become complete. 



It is very curious that the fox, so nearly allied to the 

 dog in appearance, and which also eats rabbits, never has 

 the Tienia serrata, but this animal nourishes other worms. 



