﻿MARSHALL ISLANDS ECHINODERMS — CLARK 291 



Family ACANTHASTERIDAE 

 Genus ACANTHASTER Gervais 



ACANTHASTER PLANCI (LInne) 



Asterias planci LiNNfi, Systoma naturae, eel. 10, p. 823, Appendix, 1758 (Goa 

 [Portuguese India]). 



Locality. — Bikini Atoll ; Eninman Island ; Bayer, July 17, 1947. 

 One specimen, U.S.N.M. No. E. 7391. 



Class OPHIUROIDEA 



Family OPHIOMYXIDAE 



Genus OPHIOMYXA Muller and Troschel 



OPHIOMYXA AUSTRALIS Liitken 



Ophiomyxa australis LiJTKEN, Adtlitamenta ad historiam Ophiuridarum, part 3, 

 p. 99, 1869 (Bass Strait, between Australia and Tasmania). 



Localities. — ^Bikini Atoll; one-half mile from Aomoen Island, in 

 the lagoon, in coral at 42 feet ; Brock, Kohler, and Herald, July 10, 

 1946. Four specimens, U.S.N.M. No. E. 7350. 



Rongerik Atoll ; Latoback Island, lagoon reef ; Bayer and Zimmer- 

 man, August 18, 20, 21, 1947. Four specimens, U.S.N.M. Nos. E. 7351- 

 E. 7354. 



Genus OPHIODERA Verrill 



OPHIODERA PUNCTATA, new species 



Description. — ^The disk is stellate with evenly rounded interbrachial 

 borders (dried), and is 27 mm. in diameter; the arms are 160 mm. 

 long. 



The disk is thickly studded with minute oval concretions uniformly 

 distributed over the surface but becoming smaller toward the inter- 

 radial borders; these do not extend out onto the arms, though there 

 may be a few just beyond the ends of the radial shields. The disk thus 

 resembles that of Ophiomyxa hengalensis Koehler, but the concretions 

 are smaller and end abruptly at the arm bases. The radial shields 

 are conspicuous, 5 mm. long and about 1.5 mm. broad. Their distal 

 ends are connected across the arm bases by a row of six small rounded 

 contiguous plates. 



There are no upper arm plates, but there are a few scattered rounded 

 plates on the aboral side of the first two arm segments. 



The interbrachial areas below are naked. The genital slits are long, 

 reaching nearly to the sixth spine-bearing side arm plates. Parallel 

 to the genital slits and near them is a row of eight or nine short black 

 lines at right angles to the slits, the outermost about 2 mm. long and 



