156 



BULLETIN 76, UNITED STATES NATIONAL MUSEUM 

 Specimens of Ecaslerias echinosoma examined 



tion 



2842 

 3235 

 3241 

 3278 



3281 

 3282 

 3285 

 3291 



3650 



1796 



Locality 



I Hi oo l 



i 



....do 



North ol .ii.l of Alaska Peninsula 50° 

 30" N., 162° n' W. 



do 



....do — 



.1... 



Mouth Bristol Bay, near Llaskan Penin- 

 sula, 5';° 68' 30" N., 159° 11' W. 



Okhotsk Sea (to westward of Robben 

 Island). 



Avatka Bay, Kamchatka, 52° 47' N., 

 158°43' E. 



Depth 



Fathoms 

 41 

 11 

 14 

 47 



36 

 53 

 35 

 26 



Nature of bottom 



Bottom 

 temper- 

 ature 



Pebbles 



Black stones... 



Black mud 



Fine gray sand. 



Gray sand 



Fine sand, green mud. 



Gray sand 



Black sand 



48 



Brown mud, sand 



Sand, pebbles, shells. 



° F. 

 41 



3S 

 38. 



38.2 



4! 



41.2 



X ii ru- 

 ber of 

 speci- 

 mens 



Collection 



rj.B.N.M. 

 Do. 

 Do. 

 Do. 



Do. 

 Do. 

 Do. 

 Do. 



Do. 



Albatross, 1900. 



Remarks. — This well-marked species is separated from troschelii by several 

 definite characters: (1) The well-spaced, stout, subcorneal, conical, or occasionally 

 capitate abactinal spines; (2) the unusually numerous actinal plates, there being 

 seven rows in large specimens; (3) the position of the marginal plates relatively high 

 on the side of the ray, so that the superomarginals are abactinal in position; (4) the 

 triplacantbid and diplacanthid adambulacral plates. 



A specimen from station 3291 (with R 162 mm. pi. 68, fig. 2) has the abactinal 

 spines rather more numerous, and considerably smaller than in typical specimens. 

 It is not to be confounded with E. troschelii forma acantJiostoma, because the other 

 characters are typical. 



Genus STEPHANASTERIAS Verrill 



Stephanasterias Verrill, Bull. Essex Inst., vol. 1, 1871, p. 5. Type, Asieracanthion albulus 



Stimpson. 

 Nanasler Perrier, Exp6d. sci. Travailleur et Talisman, pp. 129, 131, 133. Type, Stichaster 



albulus (Stimpson). 



Diagnosis. — Small fissiparous Asteriinae with upward of nine rays, and a closely 

 reticulate rather irregular abactinal skeleton consisting of small, lobed or elliptical, 

 imbricating plates, of which the closely imbricated 4-lobed carinals form a definite 

 fairly regular series; actinals absent; marginals low on side of ray, and, like the abac- 

 tinals bearing several short delicate spinelets; papulae simple, one to several to each 

 area, of which there are upward of four poorly defined dorsolateral and one inter- 

 marginal longiseries on either side; adambulacral plates short (compressed) dipla- 

 canthid or triplicanthid, without spine pedicellariae; adoral carina consisting usually 

 of one pair of contiguous adambulacrals increasing to three in largest specimens; 

 tube feet in four longiseries; large, toothed, and unguiculate straight pedicellariae; 

 crossed pedicellariae without enlarged terminal teeth; gonads opening low on side of 

 ray in interbrachiaJ channel, intennarginally. 



In addition to the type species, S. gracilis | Perrier) has been described from the 

 West Indian region mil' Florida, Lesser Antilles, Cuba, 56 to 200 fathoms). 



