102 



ZOOLOGY FOR MEDICAL STUDENTS 



CHAP. 



with its supple : > i nto dose proximity to the gonad the lower 



of the umbrella is tucked inwards to form a subgenital pit 

 *hich remains freely open to the sea-water by a wide 

 A hiU- the roof, separating it from the stomach and giving 

 : ,m its upper or gastral surface, is comparatively thin. 

 on as already mentioned a bright purple colour and the 



77C. 



m. 



Aurtln men viewed iVc.in l>rl<>\v. \(->. g.f, Group of gastral filaments; m, manu- 



liriutn with iiioiitli npi nin- .it tip; r, \-\\\\i canal ; rr, radial canal ; s.t, sensory tentacle ; st, stomach. 



..I' tin- iii.mubrinm have not yet grown out into long arms; 



..( tin' st.. in. nh and the (,'onads have not yet appeared; and the branching 



iplrx a-, it is in the adult.] 



'1 I rum it pass into the cavity of the stomach and thence to 

 r by the month opening. Within the curve of the gonad 

 i Iniin the floor of the stomach a row of somewhat tentacle- 

 like gastral filaments (l-'i.ns- -\~ ;m 'l 44, I, g.f). The endoderm covering 

 >\\ilr<l with .-land <ells which probably secrete digestive 

 it: their prrsemv < -on>t itutes a characteristic feature of the 



