22 BULLETIN OF THE 



ambulaeral tubercles, large ocular and genital plates, smaller spines, and 

 broad poriferous zone. — Panama. 



Eehinometra microtuberculata A. Ao. 



Can easily be distinguished from E. lucunter, to which it is closely allied, 

 by the great height of the polar diameter, the large number and uniform 

 size of the small tubercles, the arched test, and short, stout spines. Color 

 light green. — Sandwich and Kingsmills Islands. 



Eehinometra viridis A. Ao. 



The genital plates are greatly developed, smooth, occupying nearly the 

 whole of the abactinal area. Tubercles very prominent. Spines short, 

 stout. Color generally light green. — Florida. 



Eehinometra plana A. Ao. 



Flat species with a circular outline ; abactinal region less covered with 

 spines than rest of test. Spines long, sharp, equalling in length the diam- 

 eter of test. Tubercles distant, not numerous. — Hayti. 



Parasalenia A. Ao. 

 Resembles Salenia in having the abactinal system raised. There are 

 only four anal plates, as in Echinocidaris, otherwise resembles Eehinometra. 

 The genital and ocular plates are smooth. Fores in pairs, forming an irreg- 

 ular vertical line. 



Parasalenia gratiosa A. Ag. 



Outline elliptical. Tubercles arranged in two vertical rows in ambula- 

 eral and interambulacral spaces. Spines moderately long, tapering grad- 

 ually. Tubercles of ambulacra closely crowded ; miliaries small, not nu- 

 merous. — Kingsmills and Society Islands. 



Helioeidaris Desml. (emend). 

 Heliocidaris variolaris Desml. Etud. Echin. — Zanzibar. 



Toxocidaris A. Ao. 

 Toxccidaris Delalandi A. Ao. 



Syn". Heliocidaris Delalandi Ag. Cat. Rais. — Port Jackson. 



Toxocidaris mexieana A. Ao. 



Syn. Heliocidaris mexieana Ag. Cat. Rais. — Acapulco. 



Toxocidaris franciscana A. Ao. 



This species grows to a very large size. High coronal plates, large open- 

 ings for suckers. Pores arranged in arcs of nine pairs. Two very promi- 

 nent rows of large tubercles in interambulacral space. The large tuber- 

 cles of ambulacra of same size as secondary of interambulaera. Spines long, 

 tapering gradually, equalling in length two thirds the diameter of test. — 

 San Francisco. 



