102 HAWAIIAN AND OTHER PACIFIC ECHINI. 



After examining more than three hundred specimens, from the West Indies 

 and the Indo-Pacific region, I can confirm Westergren's opinion that they all 

 belong to a single species. I have collected living specimens in Torres Strait and 

 am unable to detect any character whatever to distinguish them from those I 

 have collected alive in Jamaica and Tobago. 1 On the other hand a certain speci- 

 men which de Loriol received from Mauritius and some received from Hawaii are 

 obviously different. I therefore recognize two species, but semilunaris is not one 

 of them. 



Key to the Species of Echinoneus. 



Color whitish or yellowish with a more or less marked reddish tinge; primary tubercles 



imperforate cyclostomus. 



Color more or less oh ve or greenish; primary tubercles perforate abnormaLU. 



Echinoneus cyclostomus. 



Leske, 1778. Add. ad Klein, p. 109. 



Although this widely distributed species is exceedingly variable in the 

 form of the test it is remarkably uniform in coloration. Living specimens 

 are distinctly reddish, usually pale and only rarely dark enough in life to be 

 called red, while the tube-feet are very bright red. Museum specimens, both 

 alcoholic and dry, are usually deep brownish red if in good condition but they 

 are often pale brown with no indication of red. In the West Indian region, 

 this species is known from as far north as Bermuda and as far south as Tobago. 

 It is not definitely known from the eastern Atlantic. In the Indo-Pacific region, 

 it ranges from Zanzibar to Easter Island and Hawaii. The largest recorded 

 specimen is 42 mm. long. 



The Albatross collected specimens at the following stations. 



Paumotu Islands: Fakarava, Oct. 12, 1899; Makemo, Oct, 21, 1899. 



Easter Island, Dec. 1904. 



Twenty-five specimens (mostly bare and broken). 



Echinoneus abnormalis. 



De Loriol, 1883. Mem. Soc. Phys. Hist. Nat. Geneve, 28, no. S, p. 41. 



Although de Loriol had but a single specimen of this remarkable Echino- 

 neus, his figures and description leave little to be desired. Since 1883, there 



1 Westergren (p. 48) refers to a difference between West Indian and Pacific specimens in the plating 

 of the periproct, but this difference I do not find to be constant. 



