Survey of the Animal Kingdom 307 



Fig. 112. — Feather star (Antedon sp.) of the class Crinoidea, phylum Echino- 

 dermata. Oral view showing only four of the five branched arms, each with 

 many small pinnules. The "hold fasts" attach it to the ground. 



Fig. 113. — Sandworm {Nereis virens) of tHe class Chaetopoda, phylum An- 

 nelida. A, Anterior and posterior ends (dorsal views) ; B, parapodium removed 

 from side of body and enlarged; 1 , palp; 2, terminal (prostomial) tentacle; 3, pros- 

 tomium; 4, eye; 5, lateral tentacles; 6, peristomium; 7, segment (somite) ; 8, para- 

 podium (respiratory locomotor organ) ; 9, anus; 10, anal cirrus; 11 , dorsal cirrus; 

 12, gill plate (respiratory lobe) ; 13, setae (chaetae) ; 14, notopodium; 15, neuro- 

 podium; 16, ventral cirrus; 17, aciculum. (Copyright by General Biological Sup- 

 ply House, Inc., Chicago.) 



