1913.] NATURAL SCIENCES OF PHILADELPHIA. 149 



The occurrence of this worm in wild-cats on our Atlantic seaboard 

 should be taken note of and remembered if this disease develop here. 

 Taenia echinococcus (v. Siebold). 



This material came from a female Bactrian camel which died in 

 labor from a ruptured uterus. 



The cysts were most numerous in the liver, constituting fully 

 half the bulk of that organ. The spleen was also extensively 

 involved, the lungs less so. The largest cysts in the liver were 

 sterile, showing no scolices. The specimens were observed alive, 

 and we were able to see the scolices retract the rostellum when they 

 were irritated. 



One of our microscopic specimens shows a scolex insinuating 

 itself between the lamellae of the wall of the cyst, a circumstance 

 not commonly mentioned in text-books on helminthology. 

 Taenia marginata (Batsch.). 



The opportunity has presented of seeing this parasite in the most 

 important stages of its complicated life cycle. We have seen the 

 mature worm, ovum, and cysticercus. 



The strobile or mature worm is the common tapeworm of the dog 

 and wolf. Its head is provided with a circle of booklets. Our 

 specimen was obtained from a gray wolf after a vermifuge. The 

 terminal segments are the mature ones and furnish ova to the stools. 

 In these eggs six hooks can be seen, the precursors of the future 

 rostellum of the mature worm. These eggs, if ingested by herbiv- 

 orous animals, hatch in the intestine and burrow through the 

 liver to the serous cavities of the intermediate host (a ruminant), 

 where they develop a caudal segment. This segment is cystic, 

 and into it on a long narrow neck the head is invaginated. This 

 stage is known as the cysticercus stage, and the parasite has been 

 named Cysticercus tenuicollis. We have found these cysts in the 

 Angora goats, woolless sheep, ring-tailed lemurs, Mexican deer, 

 European roe deer, mule deer, red deer, and fallow deer. It has 

 been proven experimentally by several investigators that they are 

 pathogenic for young ruminants.^ 



The occurrence of so many of the cysts aroused the suspicion that 

 our ruminants might be contracting the disease from the canines, 

 opposite whose dens some of the deer are parked. Two ex- 

 aminations of the dejecta of our canines revealed but three in- 



* Neumann's Parasites and Parasitic Diseases of the Domesticated Animals — 

 (Fleming) 1900. 



