﻿MARSHALL ISLANDS ECHLNODERMS — CLARK 269 



Note. — The spine fragment is 31 mm. long, 1.3 mm. in diameter at 

 the larger end, and 1 mm. at the smaller. It is rounded triangular in 

 section, smooth and polished, bright scarlet above, white below. The 

 lower side has five equally spaced fine longitudinal ridges. 



Family DIADEMATIDAE 

 Genus ECHINOTHRIX Peters 



ECHINOTHRIX DIADEMA (Linme) 



Echinus diadema Linn^S, Systema naturae, ed. 10, vol. 1, p. 664, No. 7, 1758 

 (Indian Sea). 



Localities. — Bikini Atoll; Namu Island, flats a little west of the 

 northern point, under loose flat coral heads; Morrison, April 4, 1946. 

 Two specimens, U.S.N.M. No. E. 7143. 



Bikini Atoll ; Bokonf uaaku Island, on ocean side of reef ; Schultz, 

 April 15, 1946. Four specimens, U.S.N.M. Nos. E. 7222, E. 7223, 

 E. 7969, E. 7970. 



Bikini Atoll; southeast corner of Bikini Island, lower intertidal 

 zone, near outer reef, under rocks; Morrison, March 7, 1946. One 

 specimen, U.S.N.M. No. E. 7006. 



Eniwetok Atoll; Ziesenhenne, February 1, 2, 1946. One specimen, 

 U.S.N.M. No. E. 7285. 



Eniwetok Atoll; Arambiru Island, ocean reef; Schultz, June 3, 

 1946. Two specimens, U.S.N.M. Nos. E. 7224, E. 7225. 



Eniwetok Atoll ; outer reef at east end of Bogen Island; Morrison, 

 May 21, 1946. Three specimens, U.S.N.M. No. E. 7536. 



Eniwetok Atoll ; outer reef flats, Pujiyoru Island ; Morrison, June 2, 

 1946. One small specimen, U.S.N.M. No. E. 7546. 



Johnston Island, outer reef ; Bayer, August 28, 1947. Three speci- 

 mens U.S.N.M. Nos. E. 7387, E. 7388. 



ECHINOTHRIX CALAMARIS (Pallas) 



Echinus calamaris Pallas, Spicilegia zoologica, . . ., vol. 1, fasc. 10, p. 31, 

 pi. 2, figs. 4-8, 1774. 



Localities. — Eniwetok Atoll ; East Rigili Island ; Morrison, May 

 30, 1946. One specimen, U.S.N.M. No. E. 7583. 



Rongelap Atoll ; intertidal ; Johnson, July 1946. One small speci- 

 men, U.S.N.M. No. E. 7611. 



Johnston Island, outer reef; Bayer, August 28, 1947. Two speci- 

 mens, U.S.N.M. Nos. E. 7220, E. 7389. 



