SOLIDUNGULA 



359 



Now, given the fact that the amphistoma has been found in the 

 horse (as your specimens prove), may we not fairly suppose it 

 possible that the animal resorts to the same mode of ridding 

 himself of this parasite as does the elephant ? and also, would 

 it not in a much more natural manner account for the large 

 quantity of gravel or sand found in the intestines than does the 

 theory of gradual accumulation ? Eeasoning from analogy, as 

 in the case of the elephant, this eating of earth in the horse 

 would be an instinctive effort on the part of the " host " to rid 

 himself of the parasite. This self-taken remedy is doubtless in 

 many cases quite effectual, though unnoticed. The fatal cases 

 are probably those in which the horse has either overdone the 

 remedy or where the 

 system was too de- 

 bilitated to carry off a 

 quantity of sand or 

 gravel that would 

 otherwise have safely 

 passed through the 

 intestines of a horse 

 in more robust health. 

 The actual fact must, 



of course, be verified 

 by careful investiga- 

 tion." 



Closely allied to 

 the Masuri is an 

 amphistome which I 

 originally named Gas- 

 trodiscus Sonsinoii, 

 but which should be 

 altered as opposite 

 (Fig. 62). It exceeds 

 \" in length and J" in 

 breadth (16 mm. long 

 by 10 broad). Its dis- 

 covery by Dr Sonsino 

 was one of the results 

 of his examination of 

 sixteen carcases of soli- 

 peds that died during 

 the Egyptian plague of 1876. Specimens having been forwarded 



e 



FIG. 62 Gastrodiscus Sonsinonis. a, Mouth; b, caudal suclcer 

 and posterior mesial cleft; c, left lip of the gastric disk; d, 

 anterior mesial cleft; e, e, gastric suckerlets; /, reproductive 

 papilla. Enlarged. Original. 



