iv PHYLUM CCELENTERATA 115 



into the interior of the body, and terminates in a free edge. 

 This tube is called the gullet or stomodaeum. Its inner 

 surface is marked with two longitudinal grooves (sgph), 

 known as the gullet-grooves or siphonoglyphes. The gullet 

 does not simply hang freely in the interior cavity, but is 

 connected with the body-wall by a number of radiating 



cst.f 



FIG. 54. Tealia crassicornis. Dissected specimen; gon, gonads; gul t gullet; 

 /. m, longitudinal muscle; Ip, lappet; ntes. I, primary, mes. 2, secondary, 

 mes. 3, tertiary mesenteries; mes. F, mesenteric filaments; mth, mouth; 

 ost. /, ost. 2, ostia or aperture in mesenteries; /. tn, parietal muscle; sgph, 

 siphonoglyphe; s. m, sphincter muscle; t. nt, transverse muscle. 



partitions, the complete or primary mesenteries (mes. '/) ; 

 between these are incomplete secondary mesenteries (mes. 2), 

 which extend only part of the way from the body-wall to 

 the gullet, and tertiary mesenteries (mes. 3), which are 

 hardly more than ridges on the inner surface of the body- 



