ARTICULATED ANIMALS. 



Blood red or coloured 



/ Breathe air 



Blood white 



No articulated limbs. Annelida, p. 63. 



Segments of the body' 

 similar no distinc- 

 tion into head, tho- 

 rax, and abdomen 

 legs twenty-four 

 pairs or more in the 

 adult breathe by 

 tracheae have no 

 wings .... 



Body divided into^ 

 head, thorax, and 1 

 abdomen have/ 



Myriapoda, p. 72. 



provided with wings I 

 respire by means 

 of tracheae . S 



Head consolidateds 

 with the thorax 

 no wings have 

 four pairs of legs 

 breathe by tracheae 

 or by pulmonary 

 sacs 



Arachnida, p. 137. 



I fHave in general five) 



x Breathe waters or seven pairs of ? Crustacea, p. 149. 

 ( jointed legs . J 



FIRST CLASS OF ARTICULATED ANIMALS 

 WORMS. ANNELIDA. 



The body of the Annelidans is composed of a succession of 

 numerous rings, all of which are merely repetitions of each other. 

 The first segment, although it differs but little from the rest, is 

 called the head. The skin is generally soft, and the rings never 

 horny or stony. Many Annelidans are entirely destitute of legs, 

 as, for example, the leech (Fig. 53); and when these organs exist 

 they are never formed of pieces jointed together end to end, as 

 they are in insects, lobsters, or spiders ; they are merely fleshy 

 protuberances, that support bunches of stiff sctcu, or bristles, and 

 are used as oars to row the animal through the water (Fig. 58). 



Most Annelidans at the anterior extremity of their body are 



