TYPES OF C@LENTERA—A.SEA-ANEMONE. 161 
complete,” ze. do not extend so far inwards. The complete 
mesenteries are attached to the oral disc above, to the side 
of the gullet, and to the base, and all the mesenteries are 
ingrowths of the body wall. The cavity of the anemone 
is thus divided into a number (some multiple of six) of. 
radial chambers. These are in communication at the base, 
so that food particles 
from the gullet may pass 
into any of the chambers 
between the partitions. 
Moreover, each partition 
is perforated, not far from 
the mouth, by a pore, 
besides which there is 
often another nearer the 
body wall. The tentacles 
are continuous with the 
cavities between the mes- 
enteries, and thus all the 
parts of the body are in 
communication. The 
mouth is usually a longi- 
tudinal slit, and its two 
corners are often richly 
ciliated. The gullet is 
marked with longitudinal 
grooves, two of which, 
the ‘“siphonoglyphes,” 
correspond to the corners 
of the mouth, and are z., Tentacles; o., mouth; @s., cesophagus; 
especially broad and c.,¢c’., apertures through a mesentery; 4.,a., 
= acontia; g., genital organs on mesentery; 
deep. Along these two ro, meen Ene filaments ; 7.2., longitudinal 
grooves, and by these two muscles; s., primary septum or mesentery ; 
. s’., secondary septum; s”., tertiary septum 3 
corners, food particles 2,’ basal disc. : 
usually pass in; but in 
some, one side is an incurrent, the other an excurrent 
channel. Occasionally only one corner of the mouth 
and side of the gullet is thus modified. The gullet 
often extends far down into the cavity of the anemone. It 
admits of a certain-amount of extrusion. The mesenteries 
bear—(a) mesenteric filaments; (4) retractor muscles; (c) 
II 
Fic. 79.—Vertical section, of a sea- 
anemone.—After Andres, 
