MOLLUSCOUS ANIMALS. 



151 



LESSON XXXI. 



MOLLUSCOUS ANIMALS STRUCTURE CUTTLE- 

 FISH POLYPI. 



THE sixth class in the animal kingdom has been 

 named Molluscous, that is, soft animals, or worms. 

 Mammalia, birds, fishes, reptiles, have a regular 

 system of bones, or a skeleton ; insects, as we 

 have already seen, have no skeleton, but consist 

 of a number of jointed parts, and are generally 

 covered with scales, or delicate feathers : the 

 worms have nothing at all resembling these, 

 their bodies being, generally, soft and naked. 

 Their flesh is white, as their blood is free from 

 colour, and they are cold to the touch. Snails, 

 leeches, worms, and shell-fish are among the mol- 

 luscous animals. 



Worms, like other cold-blooded creatures, are 

 very tenacious of life, and suffer the most severe 

 injuries without being destroyed. Many of them 



