230 



ANIMAL PAEASITES AND MESSMATES. 



of the snipe, and Fig. 62, by its side, shows the crown 

 of hooks more highly magnified. We have made these 

 drawings from worms collected from snipes some instants 

 after their death. We close this chapter on the cestodes 



Fig 61. -Taenia variabilis 

 from the snipe. 



Fig. 62. — Taenia variabilis 

 fi'om the snipe. 

 (Crown of hooks.) 



Fig. 6-3.— Tetrarhynchus 

 appendiculatus from 

 the plaice. 



with the plate (Fig. 63) of a Tetrarhynchus which is 

 usually found in the plaice. The perfect tetrarhynchi, 

 that is to say, those that are adult and sexual, inhabit 

 the intestines of voracious fishes, especially of the 

 squalidse. 



There are other worms which migrate, and even some 

 articulate animals ; but their modifications of form are 

 much fewer than in the preceding, and their changes are 

 generally restricted to simple metamorphoses. We will 

 place at the head of this chapter the Linguatulse, which 

 have so perplexed naturalists. 



We sometimes find in the nasal fossae of the dog and 

 the horse a worm resembling a leech, with a body 

 completely etiolated, which lives there entirely as a 



