32_ DEPARTMENT OF GAME AND FISHERIES No. 9 



heavier posterior to the testis, and completely filling the extreme posterior end 

 of body. Ceca bifurcate anterior to ventral sucker and continue in a wavy 

 manner to posterior end of body. 



Eggs elliptical in shape, straw-coloured, length 0.105 mm. to 0.114 mm. 

 by 0.030 mm. to 0.044 mm. wide. 



Echinostomnm callawayensis. Barker and Noll, 1015. 



Commonly found in duodenum of muskrats; length 4.98 mm. to 7.01 mm., 

 width 1.02 m.m. to 1.50 mm. Body tapers anteriorly, posterior end bluntly 

 rounded. Head collar provided with double row of spines. Oral sucker 0.07 mm. 

 to 0.15 mm. long by 0.11 mm. to 0.16 mm. wide. Pharynx short and bulbous. 

 Oesophagus bifurcates in front of ventral sucker; ceca ending blindly a short 

 distance below posterior testis. Ventral sucker muscular and well developed. 

 Cirrus sac anterior to ventral sucker; cirrus and prostate gland prominent. 



Ovary rounded to oval, situated in median line a short distance in front of 

 anterior testis. Vitellaria extend from posterior of ventral sucker to end of 

 body becoming heavier below posterior testis. Vitelline duct crosses trans- 

 versely at anterior margin of anterior testis. Excretory canal "Y" shaped at 

 posterior end of body. 



Eggs numerous, situated in region between ovar\' and posterior margin ot 

 ventral sucker, 0.0804 mm. to 0.101 mm. long by 0.041 mm. to 0.062 mm. wide. 



*Echiv.ochasnnis schwartzi. Price, 1931. 



Found in the intestines of muskrats in Ontario and described by Dr. Emmett 

 W. Price, Proceedings U.S. National Museum, Vol. 79, Art. 4, as follows: 



Body spindle-shaped in outline 1.5 mm. to 2.1 mm. long by 0.449 mm. to 

 0.620 mm. wide in the region of the anterior testis. Cuticular spines are present 

 in the anterior part of the body. These spines are scalelike and arranged in 

 alternating, transverse rows; the rows anterior to the acetabulum are close 

 together, while posterior to the acetabulum the rows are progressively farther 

 apart and the number of spines decreases; spines finally disappear near the level 

 of the posterior margin of the posterior testis. In specimens from the muskrat 

 most of the cuticular spines were missing owing to the fact that the worms had 

 been dead for several hours before fixation. Oral sucker subterminal, 0.93 mm. 

 wide, surrounded by a well-defined reniform collar, 0.248 mm. to 0.279 mm. 

 wide. The collar bears twenty-two 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 0.37 mm. to 0.41 mm. long by 0.11 mm. to 0.15 mm. 

 wide at their bases. Acetabulum circular, 0.170 mm. to 0.186 mm. in diameter 

 situated 0.542 mm. to 0.775 mm. from the anterior end of the body. Prepharynx 

 0.46 mm. to 0.93 mm. long, the length depending on the amount of contraction 

 of the anterior part of the body. Pharynx muscular, 0.108 mm. to 0.155 mm. 

 long by 0.93 mm. to 0.108 mm. wide. Oesophagus 0.124 mm. to 0.248 mm. 

 long; intestinal ceca simple and extending to near the posterior end of the body. 

 Genital pore situated immediately caudad to intestinal bifurcation. Cirrus 

 pouch poorly developed, somewhat piriform in shape, extending caudad to 

 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. Testis largely postequatorial and 

 tandem in position; the anterior testis is almost rectangular in shape, 0.155 mm. 



