NO. 5 CLARK : ECHINI OF WARMER EASTERN PACIFIC 263 



the genus are also interesting for their coloration which is notably varied 

 and inconstant, but the Panamic species is unicolor, more or less rose or, 

 according to Mortensen "light purple." Preserved specimens are dull 

 yellowish brown or the test may show a definitely purplish tint. Very 

 young specimens are yellowish, with spines and the big widely opened 

 pedicellariae, white. So far as preserved material is concerned the name 

 roseus is most inappropriate. 



Distribution. — The Velero took Toxopneustes at only 7 stations. The 

 northernmost was at Port Culebra, Costa Rica, in 3-10 fms. The southern- 

 most was at La Plata Isle, Ecuador, in 4 fms. The young specimens refer- 

 red to above, 15-23 mm in diameter, were found at Port Utria, Colombia. 

 A small adult was found at Braithwaite Ray, Socorro Island, in 20 fms 

 and a somewhat larger individual was collected at Sulivan Bay, James 

 Island, Galapagos Islands, at the same depth. This is the only record 

 from the Galapagos Islands but there is apparently no doubt about either 

 the locality or the identification. It is remarkable that Toxopneustes has 

 not been taken on the Mexican coast or at Cocos Island. It is difficult to 

 see why it does not occur north of Costa Rica but except for the Velero's 

 specimen from Socorro Island and Mortensen's statement of its occurrence 

 at La Paz, there are no records from the Mexican coast or islands. Neither 

 the Velero nor the Templeton-Crocker Expedition found even one speci- 

 men in the Gulf of California. 



Type. — No type. 



Type locality. — Acapulco, Mexico. 



Depth.— 2-30 fms. 



Specimens examined. — 22 specimens from 7 stations. 



Tripneustes depressus A. Agassiz 

 Plate 42, Fig. 18 



Tripneustes depressus A. Agassiz, 1863, p. 24. 



Mortensen, 1943, p. 498, pi. 35, figs. 1, 2; pi. 

 38, fig. 9. 

 The largest regular sea-urchin of the western coast of tropical America 

 this species reaches a horizontal diameter of 150 mm. There is great 

 diversity in form, for while the height is usually a little more than half the 

 diameter, the specimen 150 mm horizontally is only 72 mm vertically, 

 and a specimen 138 mm across is only 65 mm high. On the other hand a 

 specimen 127 mm across is 83 mm high. The height of the test thus ranges 



