198 



MANUAL OF ZOOLOGY 



SECT. 



head with its eyes and tentacles, and in other points. Many 

 possess branchia, organs which are absent as such in Nereis, 



FIG. 106. Terebella. (After Quatrefages.) 



in the form of simple or branched vascular processes ar- 

 ranged in pairs on the dorsal side of the parapodia throughout 

 the whole or a part of the length of the body, or (Fig. 106) 



