WORMS. 



351 



worms thus collected together, so as when discharged to form a 

 solid mass as large as an egg. Like the last species, they are pro- 

 pagated by ova, but sometimes these are hatched in the body of 

 the parent, so that a large worm may be seen, full of small ones. 

 This species occasions much more inconvenience than the maw- 

 worm, but still far less than the tape-worm. 



Tape-worms in the dog are of five kinds, of which the Tamfa 

 solium and Bothriocephalus latus are common to man and the dog. 

 The other kinds are not readily distinguished from these two, and 



Fig. 47. MAW-WOBM. 



all are now said to be developed from the hydatid forms found in 

 the livers of sheep, rabbits, etc. The peculiarity in the bothrioce- 

 phalus consists in the shape of the head, which has two latera? 

 longitudinal grooves, while that of the true tasnia is hemispherical 

 Professor Owen says : " The Tania solium (Fig. 48) is several feet 

 long. The breadth varies from one-fourth of a line at its anteiior 

 part to three or four lines towards the posterior part of the body, 

 which then again diminishes. The head (fig. 49) is small, and 

 generally hemispherical, broader than long, and often as truncated 

 anteriorly ; the four mouths, or oscula, are situated on the anterior 

 surface, and surround the central rostellum, which is very shorty 



