38 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



moto in 1915, and which now includes six species; these are A. 

 bellator, A. vecors, and A. rig ens, which I formerly placed in the 

 genus Astrotoma, and three new species, one from Japan, A. 

 echinaceus, described by Matsumoto, another from Bass Strait, A. 

 rugosuSj recently described by H. L. Clark, and a third, described 

 still more recently by the same author, A. rugosus. 



Astrothamnus deficiens seems to approach most closely A. 

 echinaceus on account of the presence on the disk of rather numerous 

 conical protuberances; but it is distinguished from that form by 

 the occurrence of four arm spines instead of three ; the pores of the 

 second pair already possess one or two spines, while these first appear 

 on the pores of the third pair in the Japanese species. Furthermore, 

 in A. deficiens the dental papillae are flattened, rounded at the tip, 

 and canaliculate throughout their entire length, while in the Japanese 

 species they are conical and pointed (see Matsumoto, '17, p. 86, 

 fig. 25). 



Astrothamnus deftciens can not be confused with A. rugosus H. L. 

 Clark, which was discovered by the Endeavour south of Australia in 

 between 146 and 365 meters (80 and 200 fathoms) and which is dis- 

 tinguished by its more slender and longer arms, by the number of 

 the arm spines, etc. 



Order II. LOEMOPHIURIDA. 



Family HEMIEURYALIDAE. 



OPHIOMOERIS OBSTRICTA (Lyman). 



Plate 5, figs. 3 and 4. 



Ophioceramis obstricta LYMAN ('82), p. 26, pi. 11, figs. 1-3. 

 Ophiurases obstrictus H. L. CLARK ('11), p. 250, fig. 122; ('15), p. 190. 

 Ophiomoeris obstricta MATSUMOTO ('15), p. 65; ('17), p. 140. 



Locality. Albatross station 4893 ; Eastern Sea, between 10 and 20 

 miles (18.53-37.06 kilometers) southwest of the Goto Islands; Ose 

 Saki: Light bearing N. 2 W., 10 miles (18.53 kilometers) distant 

 (lat. 32 26' 30" N., long. 128 36' 30" E.) 247 meters (135 fathoms), 

 August 9, 1906. 



One specimen (Cat, No. 41007, U.S.N.M.). 



Notes. The diameter of the disk is only 3 mm., and none of the 

 arms is complete. The individual agrees well with the figures and 

 with the notes published in 1911 by H. L. Clark, who completed and 

 corrected Lyman's original description ; I notice only that the clorso- 

 central plate is simply pentagonal and that it does not show the 

 sinuous outline represented by H. L. Clark. The first under arm 

 plate is rectangular, broader proximally than distally, as he shows, 



