PARASITOLOGY. 



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cussed the following genera: Cylichnostomum and 

 Gyalocephalus. 



Synonyms for this group are: Sclerostomum 

 tetracanthum and Strongylus tetracanthus. 



Genus Cylichnostomum. 



The cylichnostomum was so named from the re- 

 semblance of its mouth parts to a small cup, which 

 the word means. 



The general form of the body is stout. The tail 

 of the female is slender and pointed. The body has 

 transverse markings in the skin. The male is pro- 

 vided with a caudal pouch which possesses two spicu- 

 lae of equal size and shape. The intestine runs 

 straight through the body and is usually visible to the 

 naked eye especially after clarification of the speci- 

 men. Looss has apparently proven that the function 

 of the spiculae is one of copulation as he has observed, 

 in at least one case, the spiculae introduced into the 

 inner genitals of the female in a copulating pair. He 

 has also observed that the food of the cylichnostomes 

 is a colorless crumbly more or less coarsely granular 

 substance including to a varying extent particles of 

 all kinds of vegetable debris, pieces of straw, starch 

 granules and often ova and infusoria. Thus it will 

 be seen, that from a study of the intestinal contents 

 there may be some doubt as to whether they are true 

 blood suckers. The writer in his study of more than 

 300 specimens has noted in one case the ingestion of 

 two ova. 



These worms pass through their larval stage in 

 cysts in the mucous membrane of the large intes- 



