1932 ANNUAL REPORT, 1931 39 



oral sucker by short prepharynx. X'entral sucker in the anterior portion of the 

 body, 0.873 mm. to 0.979 mm. in diameter, large and muscular. Cirrus sac 

 prominent, containing a well developed cirrus, situated anterior to the ventral 

 sucker. Ovary oval or round; length 0.388 mm., width 0.585 mm. to 0.640 mm., 

 situated in median line a short distance anterior to testis. Shell gland occupies 

 the space between testis and ovary. Testis longer than wide, close together, 

 situated in the median line; anterior testis length 0.804 mm., width 0.611 mm.; 

 posterior testis length 0.989 mm., width 0.640 mm. Mtellaria extend from 

 posterior margin of ventral sucker to posterior end of body and converge a short 

 distance from posterior end. Excretory bladder well marked. Ceca bifurcate 

 in front of ventral sucker and end blindly near posterior region. 



Eggs numerous in the space posterior to ventral sucker and anterior to 

 ovary; length 0.097 mm. to 0.087 mm., width 0.063 mm. to 0.077 mm. 



Alaria mustelae. Bosma, 1931. 



Frequently found in the duodenum of mink. Body from 1.037 mm. to 

 1.22 mm. in length, concave dorsally tapering anteriorly towards oral sucker, 

 at whose sides are two projections; in living specimens these projections are seen 

 as round, pointed, retractile feelers. A short distance posterior to pharynx 

 there is a large adhesive organ which broadens to a width of 0.446 mm. to 0.485 

 mm., becoming constricted at about the posterior third of the body, gradually 

 tapering to the end where it rounds off bluntly. Uterus containing eggs, extends 

 into adhesive organ. On each side in the caudad region there is a large bilobe 

 testis. The bursa copulatrix situated in the posterior end of body posterior 

 to the testis. \'itellaria converge posterior to adhesive organ and appear to be 

 absent in posterior region. Ceca short, bifurcating from the pharynx and 

 appearing to end at anterior border of adhesive organ. 



Eggs yellow in colour, few in number, 0.116 mm. long and 0.067 mm. wide. 



Alaria americana. Hall and Wigdor, 1918. 



Found in the intestinal tract of foxes and wolves trapped in Ontario and 

 show the characteristics common to the familv. The following excerpts are 

 taken from Hall, 1918 A.\'.M.A. Journal, X'oI.'LHI., N.S. Vol. 6, No. 5, pp. 

 616-626: 



Mounted specimens less than 3 mm. long; li\e specimens appear to be 

 between 4 mm. and 5 mm. long. The oral sucker and pharynx are quite distinct. 

 Oral sucker, 0.090 mm. to 0.137 mm. in diameter; pharynx, 0.120 mm. to 0.196 

 mm. long. The ventral sucker is relatively well forward, less than its own 

 diameter from the angle formed by the intestinal ceca, measures from 0.070 mm. 

 to 0.176 mm. in diameter. Some distance posterior of the \entral sucker is the 

 attaching apparatus, a high structure, the anterior end is smoothly rounded. 

 In the median line of the vitellaria in the attaching apparatus, there is a series 

 of apparent cavities. On each side of the oral sucker are cresentic projections. 

 There is a large bilobed testis on each side of the posterior bod\-. The ovarx- 

 appears to lie partly anterior to and partly posterior to the line of union of the 

 lateral lamellar margins of the anterior body. The bursa copulatrix is less than 

 twice the diameter of the ventral sucker. The eggs in the uterus are 0.09 mm. 

 to 0.012 mm. bv 0.080 mm. to 0.086 mm. in diameter. 



