74 ENTOZOA. 



the exception of the circle of tentacles around their 

 mouths, by which they indicate their lingering affinity to 

 the Echinoderms. They have no suckers or feet, and 

 many species are marked by wrinkles encircling their 

 body, causing them to resemble earth-worms in their 

 appearance as well as in their habits. Most of them bore 

 deep holes in the sand, wherein they lodge. Others 

 conceal themselves in the crevices of rocks ; and there is 

 one species, Sipunculus Bernhardus, represented in our 

 engraving (Fig. 51), which selects the shell of some 

 periwinkle or whelk for its abode. 



FlG. 51. HERMIT SIPUNCULUS. 



CHAPTER VIII. 



ENTOZOA* (Parasitic Worms). 



LAVISHLY as we have already found the world to be 

 filled with the lower forms of animated beings, our 

 astonishment will be by no means lessened, when we 

 learn that innumerable creatures have been ordained 

 to lead a parasitic life, and to procure their nourish- 

 ment from the superabundant juices of other 

 animals; neither is this race of parasites by any 

 means deficient in numerical importance, or con- 

 structed with less careful adaptation to the situation 

 in which they are destined to reside ; they present, 

 however, little to invite our attention, and the details 

 * vr6s, entos, within ; (MOV, zoon, an animal. 



