ECHINODERMATA OF NEW ENGLAND. 



25 



B. I, b. 



Tima. Bell hemispherical with thick walls. Tubes 

 four. Tentacles, numerous, long, flexible. Ovaries rib- 

 bon-shaped on the tubes. Sense-bodies, numerous. 

 Stomach mounted on a transparent peduncle. Lips, four- 

 parted, margin with clusters of lasso-cells. 



T. Bairdii. 



MABELLA. 



SPH^ERULA. 



SKCTOR OF ZYGODACTYLA. 



YOUNG ZYGODACTYLA. 



Eutima. Bell oval, with thin walls, flexible. Tubes 

 four. Tentacles of two kinds ; four long at extremity of 

 the tubes ; pairs of small tentacles at intervals about the bell 

 margin. These latter also accompany the long tentacles 

 and may be called spurs. Stomach mounted on a slender 



ESSEX INST. BULLETIN, VOL. XXIII 2* 



