74 ZOOLOGY. 



feet, ending in tufts of stiff bristles ; and a long jointed 

 body carried straight behind, which ends in two bundles 

 of diverging spines. Such is the grotesque character under 



which our little masquer- 

 ader makes his first ap- 

 pearance on any stage. 

 After a time he drops his 

 outer garments, and as- 

 sumes a second form, wide 

 ly different from the for- 

 mer, and still sufficiently 

 remote from the ultimate 

 Fig. so. one; and it is not till the 



LARVA OF CRAB MAGNIFIED. third moult that the little 



creature, now grown to the size of a hemp-seed, begins to be 

 recognizable as a crab ; though even now he has several 

 stages to pass through several doffings of coats and trou- 

 sers before he is quite a proper shore-crab comme ilfaut" 

 As these animals increase in size, the skin becomes too 

 small to contain the body, and is cast off at intervals. 

 Moulting in the insects is confined to the larval state, 

 because when they reach the last stage, growth ceases; but 

 the Crustacea continue to grow long after the perfect 

 form is attained. While moulting, they retire to some 

 secluded place, as if conscious of their helpless condition. 



DIVISION II. Anarthropoda. 

 CLASS 1. Annelida. 



99. The Annelida (Lat. annulm, a ring) is a large class, 

 containing the leech, the earth-worm, the lob-worm, and 

 those animals which live in tubes, termed Serpul83. It 

 is distinguished from the Arthropoda mainly by the 

 absence of jointed limbs. 



The Annelida are worm-like animals, covered with a, 

 soft skin. The body is divided into a series of rings or 

 segments, which are all exactly like one another, except 



