PARASITOLOGY. 119 



Conditio7i Produced. — It becomes lodged in the mu- 

 cous membrane of the abomasum and intestines, 

 more commonly in the former location. Upon ex- 

 amination of the infested tissue small nodules, the 

 size of a pinhead or millet seed, will be observed. 

 These nodules may be slightly depressed in the cen- 

 ter. If this membrane be placed in a compressor 

 glass it will be found to contain the larva or adult 

 worm. 



Sympto77is. — The symptoms are the same as those 

 produced by the Strongylus Contortus. 



Treatmeiit. — The same as for the Strongylus Con- 

 tortus. 



STRONGYLES OF THE HORSE. 

 The Strongylus-Armatus Group. 



In the group of parasites commonly known under 

 the name of Strongylus armatus will be discussed the 

 following genera: Sclerostomum and Triodonto- 

 phorus. 



Genus Sclerostomum. 



The mouth-collar is formed by a continuation of 

 the skin and at its upper part is split into a 

 delicate fringe-like crown. See figure 1, 4 and 6, 

 Plate 9, and 9 in Plate 9. The inner part of 

 this mouth-collar rests on the anterior border of the 

 mouth-capsule. The skin is thick. The head is pro- 

 vided with papillae and the four sub-median are 

 marked by a short point composed of the chitinous 

 substance of the mouth-collar and projecting at the 

 base of the anterior leaf-crown. The 'fiibers of the 

 papillary nerves terminate immediately beneath them. 

 The lateral papillae are not provided with these points 



