168 



ZOOLOGY 



The mouth is situated at the end of a short manubrium (miib. ) leading into a 

 wide stomach, from which go off four very broad per-radial pouches (rad. p. ), 

 occupying the whole of the four flat sides of the umbrella, and separated from one 

 another by narrow inter-radial septa or partitions placed at the four corners. 

 These pouches are equivalent to wide radial canals, and the partitions between 



on. 



end. lam 



circ. 



Fro. 120. C 

 pass:. 



C, transverse secti 

 longatioii into the 



gonads ; i. lappet; num. iu;uuu>rmm ; nm. / 

 vl. velarium. (After Glaus, somewhat altered.) 



them to a poorly developed endoderm lamella (end. lam.). At the margin of 

 the umbrella the pouches communicate with one another by apertures in the 

 septa, so that a kind of circular canal is produced (circ. c. ). Near the junction 

 of the gastric pouches with the stomach are the usual four groups of gastric 

 filaments (y. f. ). 



The gonails (//OH.) are four pairs of narrow plate-like organs, attached one 

 along each side of eacli inter-radial septum. The nervous system takes the form 



