SHALLOW- WATER STARFISHES 1$! 



appearance, due to the large number of small, even spinules, and 

 their peculiar transverse arrangement on the sides of the rays ; the 

 same reticulate arrangement of slender dorsal ossicles; and essen- 

 tially the same arrangement of the marginal ossicles and spines. 

 Superomarginal ossicles seem to be equally obscured in both. Both 

 also have three corresponding forms of pedicellariae. In both, 

 the forcipulate ones are unusually stout and blunt ; in both there are 

 adambulacral forficulate pedicellariae with acute tips, and also a 

 much larger dermal kind, "nearly cylindrical," with wide obtuse 

 valves. The last-named form is very unusual and is a strong indi- 

 cation of specific identity. The principal difference seems to be that 

 in C. cribraria the adambulacral plates are described as having two 

 spines, while in C. spitzbergensis they bear alternately two and three 

 spines. The differences may well be due to the much larger size 

 of the latter, which was about twice as large as the former. 



After carefully comparing specimens of both, my conclusion is that 

 they are identical but variable. 



Several young specimens of cribraria of different sizes were sent 

 to me by the United States National Museum (No. 6123). These 

 were taken in the Arctic Ocean, north of Alaska, near Icy Cape, in 

 10 to 15 fathoms, mud and sand. Smith, 1874; coll. W. H. Dall, No. 

 1 212. One of these furnished the details shown in text-figure, 

 No. 7. The larger of these (greater radius, 30 mm.) agrees almost 

 exactly with a specimen of similar size from Spitzbergen, 17 to 23 

 fathoms, July 25, 1899, sent by the Museum of Comparative Zoology. 

 Another, from Greenland, sent with last, is smaller and agrees well 

 with the smaller Alaskan specimens. These were labelled as A. 

 grcenlandica, but do not agree with typical specimens of the latter 

 sent to me by Dr. Chr. Lutken. 



Genus Evasterias Verrill, nov. 



A group of long-rayed, diplacanthid starfishes with a rather small 

 disk and a reticulated dorsal skeleton, bearing numerous small spines 

 arranged in a reticulated or subreticulated pattern, or in transverse 

 combs, and having several rows of imbricated interactinal ossicles, of 

 which, in the adult, there may be three to five or more rows. Type, 

 E. troschelii (Stimpson). (See also p. 51.) 



EVASTERIAS TROSCHELII (Stimpson). 

 Plate xxn, figures I, 2; plate xxv, figures I, 2 (type) ; plate xxvi, figures I, 2 



(typical) ; plate LXII, figure I (variety) ; plate cvi, figures I, 2 (young). 

 Ast erica troschelii STIMPSON, Proc. Boston Soc. Nat. Hist., vni, p. 267, 1862. 



Verrill, Trans. Conn. Acad., n, part 2, p. 326 (no descr.) 1868. Perrier, 



