H 

 ITohthuricr 



JTntedon, Penfacnnus. 



, as 



^ anus 

 Fig. 3S2.— Diagram of the course of the alimentary canal in various Echinoderms. The 

 body is viewed from tlie oral side, ind, ms, Mesenteries ; us, food-grooves or aiiilmlaeral furrows 

 of the tegmen calycis ; m, madreporite ; x, coiiunencement of the backward coil of the intestine ; 

 ii first, io second (backward) coil of the intestine ; s, siphon, accessory intestine ; 1 and 2 (in F) 

 the two points at which the accessory intestine enters the principal intestine ; si, free portion of 

 the accessory intestine ; .s.i, portion of the same in contact with the principal intestine ; coec, in- 

 testinal ccecum. [Combined from several sources.] 



