564 T^ENIA MARGINATA AND CYSTICERCUS TENUICOLLIS. 



lating. The last proglottides have the form and size of those in the 

 smaller human tape-worms, having a 'breadth of 4 to 5 mm., and a 

 length of 9 toll mm. They contain a uterus, which is characterised partly 

 by the shortness of the median stem, and partly by the small number (at 

 most eight) of lateral branches, which have, however, strong and wide- 

 spread ramifications above and below. Tlie emfoyonic shells are round 

 (O036 mm.), thick, and covered by a distinct layer of rods, as in T. 

 solium. 



The worm thus shortly described was first made known to us 

 by Kiichenmeister's breeding experiments. He termed it Tcenia e 

 Cysticerco tenuicolli ; after which I showed that it was identical with 



FIG. 304. Hooks of Tcenia marginata. ( x 280.) 



the T. marginata described by Batsch from the wolf. This Krabbe 

 and Kiichenmeister confirmed. The related bladder-worm (Cysticercus 

 tenuicollis) lives sometimes alone, sometimes in groups in the omentum, 

 and more rarely in the liver and other viscera, especially of ruminants 

 and swine. 1 It has an oval form, and an ap- 

 preciable, sometimes considerable, size. In the 

 larger specimens the anterior end of the bladder 

 is drawn out into a long, slender, neck-like pro- 

 cess, which bears the parenchymatous worm-body, 

 and encloses it in a sheath, when both are re- 

 tracted within the bladder. Then it forms a more 

 FIG. W$. --Cysticercus or i ess i ong r ibbon, hanging into the cavity of the 



tenuKolhe, after Bremser f 



(half size). bladder, in which it sometimes floats freely, or is 



at certain points connected with the wall. 



Since the Cysticercus tenuicollis is not a rarity in animals used as 

 food (also in deer and roes), and sometimes grows to the size of a 

 child's head, 2 we may readily suppose that it has been known for 



1 Africa is also a home of the Cysticercus tenuicottis, as I have proved by the examina- 

 tion of a Cysticercus from Potamochcerus penicillatus, for which I am indebted to Dr. 

 Spencer Cobbold of London. 



a Kuchenmeister even credits the bladder- worm with a length "of five feet," " Para- 

 siten,*' second edition, p. 138. 



