334 BULLETIN ~Q, UNITED STATES NATIONAL MUSEUM. 



Genus LOPHASTER Verrill. 



Lophastcr Verrii.i., Amer. Journ. Sci. and Arts, ser. 3, vol. 16, 1878, p. 214. Type, Solaster furdfer 



Diiben and Koren. 

 Sarkastcr LuDwiG,Mem. Mue. Comp. Zool., vol. 32, July, 1905, p. 185. Type Sarkaster validm 



Ludwig. 



Diagnosis. — Five-rayed Solasteridfe with cruciform or lobed abactinal paxilli- 

 form ])latcs (\\'ithout intermediate connecting ossicles) forming a quadrate or polygo- 

 nal meshed skeleton; with two well-developed series of marginal paxillse, and with 

 usually a single series of spaced actinal intermediate plates extending far along ray, 

 with or \\dthout a paxiUiform tuft of spinelets; adambulacral plates with a furrow 

 comb usually webbed, and with an actinal comb of spines, often oblique, beliind the 

 furrow scries. 



Remarks. — Much may be said for merging tliis genus with Solaster. The type 

 is, I beheve, more distinct than Crossaster, and is kept separate for convenience, 

 and in the beUef that, although close to Solaster, intergrading species have not been 

 demonstrated. 



A curious misapprehension has for some reason grown up around tliis genus. 

 Sladen states in his key that there are no actinal intermediate plates along the ray, 

 and Ilamann in Bronn's Thierreich follows Sladen. A specimen of L. furdfer from 

 the Kara Sea, which I have, has a single series of spaced actinal intermediate paxillfe 

 placed alternately with the inferomarginals, extending very nearly to the tip of the 

 ray (to within 6 mm., R being 45 mm.). Specimens of L.furciUiger vexator described 

 below are similarly provided, although in some specimens they are suppressed 

 except for widely-spaced plates on the outer part of the ray. L.furciUiger vexator is 

 an undoubted Lopliaster, and is beheved to intergrade with furcilliger in deeper 

 water; with the latter Sarhaster validiis is either identical or closely related. It fol- 

 lows, therefore, that Sarkaster can not be maintained, for its alleged distinguishing 

 character is shared by Lofhaster. Even if in Lopliaster furdfer intermediate plates 

 are not always present on the ray, the case against Sarkaster is not altered. 



LOPHASTER FtTRCn-LIGER Fisher. 

 PI. 79, figs. 1, 2; pi. 114, figs. 1, la—g; pi. 116, fig. 5. 

 Lophaster furcilliger Fisher, Bull. Bur. Fisheries for 1904, vol. 24, June 10, 1905, p. 312. 



Diagnosis. — Rays five. R = 70 mm., r=16 mm., R = 4.38 r. Breadth of ray at 

 base IS mm. or a httle less than one-fourth R. Disk rather small, rays long, tapering 

 from narrow base very gradually to pointed extremity, ambulacral furrow wide 

 and shallow; tube feet with small sucking disk. As compared with L. furdfer, rays 

 narrower and longer, abactinal skeleton more open, paxiUse much slenderer, higher, 

 with longer and more dehcate spinelets having only two or three, less often four 

 sharp points; marginal paxillte higher, more spaced, actinal interradial areas much 

 smaller with fewer plates, which with the intermediate plates along ray have more 

 delicate spinelets; adambulacral spinelets longer and more delicate, and the series 

 as wide apart as length of a series, not close together. 



Description. — Abactinal surface beset with well-spaced paxillae, which have 

 rather long (2 to 3 mm.) slender pedicels, with a capitate summit beset with two 



