416 PROCEEDINGS OF THE ACADEMY OF [1890. 



one in five or six was infested with the larval distomas enclosed in 

 sporocysts, often in large number, embedded in the liver and 

 associated genital gland. The larvae always appeared in the 

 distoma-form and never as a cercaria. They exhibited no trace of 

 genital organs, and were all provided with a conspicuous style, in 

 the forehead as it were, ready for penetration into their as yet un- 

 known future host, 



25. Distomum centrappendiculatum. 



Distomactppeudlmkda Leidy, Proc. A. N. S. 1877,202; not Dlsto- 

 mum appendiculatum Rudolphi. 



26. Tetracotyle typica Diesing. 



Body flattened obpyriform, with an oral, a ventral central and an 

 anterior lateral pair of bothria. Length 1-125 to 1-25 mm. long by 

 0-95 to 1-125 mm. broad. 



Encysted in the liver and genital gland of Lymnaea catascopvum 

 and Physa heterostropha. Sixty-five specimens were obtained from 

 a single Physa. 



27. Cercaria platyura n. s. 



Body elongated hemielliptical, widest and truncate behind ; head 

 rounded ; oral acetabulum large and spherical, with a strong style 

 in the upper lip ; ventral acetabulum central, smaller than the for- 

 mer. Tail nearly as long as the body, stout, tapering, corrugated 

 and with a broad, costate, lateral membrane. Length 0-8 mm. ; 

 body 0*4 by 0-12 mm. ; tail 0'36 by 0-06 mm. at base, breadth with 

 membranous alae 0-14 mm.; oral acetabulum O'OS mm.; ventral 

 acetabulum 0*06 mm. 



Found free in a pool, with Lymneus, at Fort Bridger, Wyoming. 



28. Cysticercus tenuicollis Rudolphi. ^The Larva of Taenia marginata Batsch. 



1. A specimen enclosed in a spherical cyst an inch in diameter 

 attached to the paunch of a young sheep, Ovis aries. Cysticercua 3 

 inches long with terminal cyst an inch in diameter ; the retracted 

 head and neck an additional inch in length. Submitted by Dr. 

 J. Cheston Morris. 



2. A specimen from the vagina of a Sheep, measured 5 J inches in 

 length with the terminal cyst over an inch in diameter. 



3. A specimen enclosed in a sac an inch in diameter attached by 

 a pedicle two inches in length to the liver of a Monkey, Semnopith- 

 ectis entellus. The worm was 22 mm. long ; the body 8 mm ; the 

 terminal cyst 14 mm. in diameter. The retracted head 1 mm. broad ; 



