4 



PROCEEDINGS OF THE NATIONAL MUSEUM 



VOL. 79 



before fixation. Oral sucker subterminal, 93/x wide, surrounded by a 

 well-defined reniform collar, 248/i to 279fi wide. The collar bears 

 22 spines arranged in a single row which is interrupted dorsally by 

 a space as wide as the oral' sucker. Four of these spines, two on each 

 ventral lobe, are slightly more aboral than the others ; the more median 

 of these spines is 37/x to 41/x long by llju. wide at the base, while the 

 others are from 44/* to 51/x long by 11/* to 15/* wide at their bases. 

 Acetabulum circular, 170/* to 186/t in diameter, situated 542/i to 775/t. 

 from the anterior end of the body. Prepharynx 46/t to 93/* long, 

 the length depending on the amount of contraction of the anterior 

 part of the body. Pharynx muscular, 108/* to 155/i long by 93/* to 

 108/* wide. Esophagus 124/t to 248/* long ; intestinal ceca simple and 

 extending to near the posterior end of the body. Genital' pore situ- 

 ated immediately caudad of intestinal bifurcation. Cirrus pouch 

 poorly developed, somewhat piriform in shape, extending caudad to 



mm 



PlGCRB 2. ECHINOCHASMDS SCHWAETZI. VBNTEAL VIEW OF SPECIMEN FROM MUSKBAT 



near the posterior margin of the acetabulum, and containing a large 

 seminal vesicle showing a distinct constriction near its anterior end, 

 a poorly defined prostate, and a short ductus ejaculatorius. Testes 

 largely postequatorial and tandem in position; the anterior testis is 

 almost rectangular in shape, 155/i to 279/* long by 310/* to 434/i wide ; 

 the posterior testis is irregular to aMiost spherical in outline, 186/i 

 to 310/t long by 263/i to 372/* wide. Ovary ovoid, 108/i to 124/i by 

 124/1 to 170/*, situated slightly to the right of the median line and with 

 its long axis diagonal to the long axis of the body. The vitellaria 

 are composed of large follicles distributed as in the other members 

 of the genus ; the follicles extend anteriorly to the level of the poste- 

 rior margin of the acetabulum or slightly beyond, but never farther 

 forward than the anterior margin of the acetabulum. Uterus short, 

 consisting of a few irregular coils almost filling the intercecal space 

 between the anterior testis and acetabulum, and containing from 4 

 to 40 eggs. Eggs oval, 68/* long by 45/* wide, with yellowish brown, 

 thin shells. 



Hosts. — Ondatra zibethica and Canis familiaris. 



Location. — Small intestine. 



