230 



MARINE INVERTEBRATES 



radatnJi 

 ring ves 



ri.bl-vee 

 poL VRG 

 stum, 

 inl vea 



int 



Internal organs of a Holothwrian, as seen when the body-wall is divided along the middle of 

 the dorsal surface: b.w., body- wall ; circ. DIMS., circular layer of muscle ; cl., cloaca; cl. op., cloacal 

 opening with five teeth ; eu. org., Cuvierian organs; gen. ap., genital aperture; gen. du., genital 

 duct; gen. gl., genital gland; int., intestine; inter, oss., interambulacral ossicles; int. ves., in- 

 testinal vessels; long, mus., longitudinal band of muscle; mad. can., madreporic canals; ines., 

 mesentery ; pol. ves., Polian vesicles ; rod. amb., radial anibulacral vessel ; ri. bl. ves., ring blood- 

 ve.s.sel j resp., respiratory trees ; rinq-ves., ring-vessel of tUQ auibulacral system ; stem., stomach. 



