-308 BULLETIN OF THE 



Othilia spinosa Gray, Synops. 



Syn. Echinaster spinosus M. T., Syst. 

 Littoral, to 6 fathoms. 



Othilia braziliensis Ac 



Syn. Echinaster braziliensis M. T., Syst. 

 Littoral, to 5 or 6 fathoms. 



Aster ac an thion mexicanum Lutk. 

 From 80 to 120 fathoms. 



Asteracanthion tenuispinum Lutk. 

 Syn. Asterias tenuispina Lam. 

 Asterias atlantica Ver., Trans. Con. Ac. 

 From 120 to 174 fathoms. 



With the exception of the Pteraster and Asteracanthion tenuispinum, 

 the bathymetrical and geographical distribution of the Star-fishes does 

 not show any striking features. The presence of a northern and of a 

 Mediterranean species in Florida is fully in accordance with the 

 results derived from other classes ; as with Echini and Ophiurans, 

 we find the young in much deeper water than the adults. This is particu- 

 larly well shown in a series of Pentaceros gigas ; the smallest specimens 

 (Pteraster-like in shape) are from 128 fathoms, more advanced stages 

 (Goniodiscus-like) are from 68 fathoms, a still more advanced stage 

 from 42 fathoms. The same is the case with Luidia clathrata and 

 Astropecten antillensis. 



Cambridge, October, 1869. 



