96 ANIMAL PAEASITES AND MESSMATES. 



in this animal, may find its way into the liver of man, 

 or into that of the hare, the rahbit, the horse, the 

 squirrel, the ass, the pig, the ox, the stag, the roebuck, 

 and different species of antelope. It is to be remarked 

 that all these animals have a vegetable regimen. By 

 drinking the water which contains the cercaria of this 

 species, they grow infested by this singular lodger. The 

 large Echinorhyncus {E. Gigas) has been found in the 

 dog, and the pig, perhaps in the phocinae ; and instances 

 are mentioned in which it has even migrated into man. 

 The Gordius aqiiaticus appears to live and develop itself 

 in different species of insects ; and among the articulated 

 parasites, we meet with the Ixodes ricinus, commonly 

 called the tick, on the dog, the sheep, the roebuck, and 

 the hedgehog ; and instances are given of its presence 

 on man. It has been long since proved in menageries 

 and zoological gardens, that the Acarus of the camel is 

 able to give a cutaneous disease to man. 



As we have before said, there are many parasites 

 which require to be studied in order to determine the 

 host peculiar to each of them; although parasites 

 sometimes lose their way, and introduce themselves into 

 the wrong neighbour, yet they can live there but a short 

 time. Instances have been known, in which the larvae 

 of flies have penetrated into man accidentally by the 

 mouth or the nostrils. Eeptiles have been known to 

 live a certain time in the stomach. A German physio- 

 logist, Berthold, professor at the University of Gottingen, 

 has given an account of all those which have been 

 found under such circumstances, and the number of 

 them is considerable ; he has written a memoir on the 

 abode of living reptiles in man. 



