STAEEISHES OF THE PHILIPPINE SEAS. 467 



2 suboral in a series parallel to median suture. The inner suboral 

 stands on the margin of plate close to the inner marginal spine, but 

 is much thicker than the latter, and in turn is a little less robust, 

 though longer, than the outer suboral. The mouth plates have all 

 been more or less rubbed and injured. 



Actinolateral membrane broad, rather thin, deep brown in color. 

 Where this colored layer has been rubbed off a gray, finely fibrous 

 layer is revealed. The longest actinolateral spines are the twelfth 

 to seventeenth or eighteenth, which are about subequal and 13 or 

 14 mm. long. 



Type.— C^i. No. 37018, U.S.N.M. 



Type-locality. — Station 5428, Sulu Sea, off eastern Palawan (lat. 9° 

 13' N. ; long. 118° 51' 15" E.), 1,105 fathoms, green mud, bottom tem- 

 perature 49.7° F. ; 1 specimen. 



Distribution. — Known only from the type-locality. 



Remarks. — The description of H. puUatus ^ does not state the num- 

 ber of series of pseudopaxillae to each ray, nor whether those of the 

 radial regions are so reduced in size as to be considered rudimentary. 

 Neither the figures nor description indicate the presence of spiracula 

 which are so plentiful in hartschi. The lateral areas of small spi- 

 racula, marked by a brown pigment against a grajdsh ground, are 

 very conspicuous in the Philippine form, and probably not present 

 in puUatus. In hartschi the adambulacral spines are more attenuate 

 at the tips than in puUatus., while the aperture papilla is slightly 

 broader. In proportion to the size of the aperture papilla and the 

 base lines of the furrow comb, the actinolateral spines of hartschi are 

 decidedly smaller at the base than are those of puUatus. 



Hymenaster hartschi seems to be a representative species occupy- 

 ing the deep basin of the Sulu Sea. Whether it is to be regarded as 

 a distinct species or only as a geographic race of 11. puUatus will 

 depend upon the value assigned to the absence of spiracula in pul- 

 latus. The characters of the paxillae are very positive in hartschi.^ 

 and upon certain important points information in regard to puUatus 

 is lacking. H. puUatus was dredged by the Challenger at station 

 218 off the north coast of New Guinea, southwest of the Admiralty 

 Islands, in 1,070 fathoms, blue mud. 



This species is named for Dr. Paul Bartsch, of the United States 

 National Museum, who was naturalist during the Philippine cruise 

 of the Alhatross. 



Genus HYMENASTERIDES Fisher. 

 Eymenasterides Fishee, 1911a, p. 425. 



Diagnosis. — In general structure similar to Hymenaster but with 

 two kinds of adambulacral plates alternating; (1) prominent plates 



I Sladen, 1889, p. 519. 



