426 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



there are 5 rays, as none of the disk is present. The species differs 

 from A. diaphana in having more numerous spinelets in the abacti- 

 nal tufts, much more numerous papular pores, these being arranged 

 in 2 irregular, sometimes zigzag, series along either side of a narrow 

 median radial area. The abactinal plates usually have, near base of 

 ray and radius, 3 tufts of spinelets, of which the median is large and 

 carries l2 to 20 delicate sharp spinelets, and the small lateral tufts 

 only 2 to 5. Sometimes there is 1 small tuft. Near the margin, only 

 the large tuft persists. The furrow spinelets are 6 or 7 (6 in di- 

 aphana) . Subambulacral spinelets proximally 5, then 4, then 3. The 

 median 1 or 2 are much the stoutest. Actinal intermediate spinelets 

 3 to 5, in a single series, basally webbed, the median 1 or 2 much the 

 stoutest. 



Sladen states that in diaphana the papular pores are large and 

 spiraclelike, margined by 7 or more plates, each of which bears a 

 small comb of rather elongate spinelets directed over the opening. 

 In the present species the pores are margined by 3 to 5 plates. It is 

 possible that on the disk there were more. 



Family ECHINASTERIDAE Verrill (restricted). 

 Genus ECHINASTER Mullet and Troschel. 



Evhinaster Mulleb and Tboschel, 1840a, p. 102; 1840&, p. 321. Type, 

 Asterias seposita Lamarck (not Retzius, 1783) =Asterias sagena Ret- 

 zius, 1805, first species (designated, Fisher, 1913?>). — Fisheb, 1911d, 

 p. 260; 191«&, p. 194.— VEEEII.L, 1914a, p. 206 {+OthiUa) ; 1915, p. 35 

 i+Othilia). 



Rhopia Geat, 1840, p. 282. Type, R. seposita Gray=J.. sagena Retzius, not 

 A. seposita Retzius as stated by Gray (designated, Fisher 19136). 



The genus Echinuster Miiller and Troschel (April, 1840) is usually 

 understood to include Othilia and Rhopia Gray (December, 1840). 

 In a key to the genera of Echinasteridae in Asteroidea of tRe North 

 Pacific, etc. (1911, p. 259), I recognized Othilia for those species 

 which have, in addition to iftactinal papulae, also intermarginal 

 papulae or both intermarginal and actinal papulae, while the name 

 Echinaster by implication was reserved for Echinxister sepositus and 

 allies, in which there are neither intermarginal nor actinal papulae. 

 Professor Verrill, in a letter, dissented from this course. I pub- 

 lished a short note (1913&) in explanation of my point of view, 

 which is here largely reproduced. 



Professor Verrill considers that Asterias spinosa Retzius (1805),^ 

 which I made the type of Othilia Gray, is really the type of the 

 previously described Echinaster, by designation (Miiller and Tres- 

 is This name Is preoccupied by Asterias spinosa Pennant, 1777 [= Asterias glacialis, 

 1758]. Asterias echinophora Lamarck, 1S16, is the tenable name for the species. 



