PHYLUM CCELENTERATA 



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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 



i-ncfi 



ost. f 



Fig. 54. — Tealia crassiCOmis. Dissected specimen; gon, gonads; gui, gullet; 

 /. m t longitudinal muscle; Ip, lappet; mes. 1, primary, tries. 2, secondary, 

 vies. 5, tertiary mesenteries; mes. F, mesenteric filaments; tilth, mouth; 

 ost. /, ost. 2, ostia or aperture in mesenteries; /. t>i, parietal muscle; sgph, 

 siphonoglyphe ; $. tn, sphincter muscle; t. tn, transverse muscle. 



partitions, the complete or primary mesenteries {mes. i) ; 

 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- 



