12 THE REPORT UPON No. 36 



The internal parasites continue to be the main source of mortality with 

 fur-bearing animals. Practically no animals trapped in the wilds appear to be 

 free from them. Different species have been identified in the fox, mink, 

 lynx, raccoon, fisher, beaver, wolf and muskrat. 



The mink is much subject to the trematode species and no doubt becomes 

 infested through his aquatic habits. Fish and snails are probably the inter- 

 mediate host of a number of mink parasites. Three different species of treraa- 

 todes have been identified in the mink. One new species, the Parametorchis 

 canadaensis, was discovered at the Fur Farm. This species is found in the gall- 

 bladder. The Plagiorchis proximus is found in the duodenum. A very small 

 trematode which appears to be related to the salmon poisoning fluke, Nano- 

 phyetus salmincola, is found in the small intestines. A worm of microscopic 

 proportions of the Capillaria sp., and a new species of tapeworm, not as yet 

 named, are also found in the small intestines. Two worms of particular interest, 

 one of the Dioctophyme renale, and one of the Oslerus, or a related form, have 

 been found in mink. The Dioctophyme renale inhabits the kidney and causes 

 large deposits of bony substances in that organ. This worm is particularly 

 destructive. The Oslerus infests the pulmonary veins and has a peculiar knot- 

 like structure and seems to adhere firmly to the outer membrane of the vein. 



With the muskrat, two types of flukes, intestinal and liver, are very com- 

 monly found. The Echinostomum coalitum infests the intestines and is 

 found in enormous quantities. One interesting parasite infesting the muskrat 

 are larval cestodes, found in the peritoneal cavity of the Taenia sp. The 

 Cysticercus fascolaris, the larval form of taenia Taeniaeformis, is commonly 

 met with, also H. evaginata. 



Ascaris sp. have been identified in the raccoon, also the immature form 

 of the Physaloptera sp. 



In the lynx, Toxocaris mystax, the round worm of the cat, was found. 



Two trematodes, of the species Echinostoma and Hemistomum, were 

 found in the fisher. 



Platypsyllus castoris, a type of parasitic beetle, was removed from beaver. 



Crown Game Preserves 



Following is a list giving description, location and area of the Crown Game 

 Preserves in Ontario as at December 31st, 1929: 



Crown Game Preserve Location Acreage 



Abbey Dawn Frontenac County 300 



Anderdon Township Essex County 1,200 



Bobcaygeon Victoria and Peterborough Counties 1,700 



Boyd York County 300 



Caverly Elgin County 25 



Chapleau Algoma and Sudbury Districts 1,824,000 



Chippewa Thunder Bay District 2,728 



Conroy Marsh Renfrew County ooo 



Darlington Durham County 298 



Dumfries Waterloo and Brant Counties 7cn 



Dundas Marsh Wentworth County ^'I^n 



Eden Wellington County 1 .*70 



Eugenia Grey County if nnn 



Falcon Kenora District ^^'.rl 



Glendale Wentworth County. 



Glen Elm Halton County 



Gloucester Carleton County . . . 



Hiawatha Algoma District. 



450 

 325 

 200 

 160 



Hope Durham County 1,920 



