378 SYNOPTIC COLLECTION. 



In the process of growth the animal elongates (No. 

 938) and the body wall becomes constricted, forming 

 ridges or raised rings throughout nearly its whole length. 

 The mouth parts are represented by two pairs of horny 

 hooks only, on either side of the mouth (No. 938 ; PI. 

 937, fig. 5), "and the feet have wholly disappeared. In 

 addition to this loss of external organs, Linguatula is 

 without a heart, tracheae, or lung sacs, respiration being 

 effected by the skin. 



The life history of Linguatula proboscidea Rud., is not 

 so well known as that of L. taenioides Rud. The mature 

 female of the latter species is found in the nasal passages 

 of the dog where the eggs are laid. These are expelled 

 by sneezing and are scattered on the grass. The latter is 

 eaten by some herbivorous animal. The embryo develops 

 into the four-footed larva which has mouth parts adapted 

 for boring. By means of these the larva finds its way to 

 the liver or lungs of its host and there becomes encysted. 

 When the herbivorous animal is eaten by a dog the cyst 

 is ruptured and the mature female makes its way to the 

 nasal passages, when the process is repeated. 



MALACOPODA. 



Section 14 (in part). 



One of the most interesting animals is Peripatus (No. 

 939, P. edwardsi Blanch, or P. trinidadensis ; PI. 940, 

 figs. 1-4, P. capensis, drawn from life, life size). It is a 

 synthetic form, combining characters of Mollusca, Anne- 

 lids and Malacopods. It is "an animal of striking 

 beauty," says Adam Sedgwick. 1 "The exquisite sensi- 



. Morphological Lab., Univ. Cambridge, IV, part 2, 1888, 

 P- 155- 



