1932 



ANNUAL REPORT, 1931 



37 



in posterior half of body; 0.388 mm. long by 0.194 mm. wide. Excretory canal 

 well developed and "Y" shaped. 



Eggs scanty, yellowish brown in colour, 0.086 mm. to 0.107 mm. long by 

 0.054 mm. to 0.068 mm. wide. 



Dioctophyme renale (Goeze, 1782), (Stiles, 1901). 



The largest and most frequently found nematode affecting mink. Females 

 blood red, from 150 mm. to 650 mm. in length. Males brown, from 90 mm. to 

 150 mm. in length. Inhabits the kidney and occasionally the abdominal and 

 thoracic cavities. In the later stages of infestation the kidney is greatly 

 encysted. The cyst is filled with a brownish fluid containing from one to six 

 worms which are associated with a characteristic bony deposit. 





Fig. 14. — Dioctophyme renale: Two males and four females. Cystic kidney showing bony 

 deposits. (Original, Law and Kennedy.) 



The following taxonomic description is according to Yorke and Maplestone: 

 Male: bursa copulatrix bell-shaped, muscular and not supported by rays; 



spicule single and long. Female: tail blunt; anus terminal; \'ulva in the anterior 



part of the body; one ovary. 



Oviparous, eggs ellipsoidal, brown in colour, shell thick and co\"ered by 



small depressions except at the poles which are homogeneous, they contain a 



segmented ovum at the time of deposition. 



Echinostomiim armigerum. Barker and Irvine, 1915. 



Commonly found in the duodenum of muskrats. Varies considerably in 

 length and breadth in different specimens; length 10.0 mm. to 13.0 mm., width 

 1.0 mm. to 2.25 mm. Body tapers slightly at anterior end, posterior ^nd being 

 bluntly rounded; flesh-coloured and comparatively heavy. Oral sucker, 0.291 

 mm. in diameter surrounded by a kidney-shaped head collar with numerous 

 spines. Pharynx muscular, length 0.271 mm., width 0.222 mm., connected with 



