428 y^^' W. K. Fislicr 07i new 



witli thin disk and deciduous, slender, flexible rays, thin 

 delicate abactinal integument, and very fragile spines. 

 Diiliering from B. exilis in having 25 to 30 cost^e which 

 extend at least tJiree-fourths the length of ray, comparatively 

 few, widely spaced, embryonic, abactinal disk-plates bearing 

 1 or occasionally 2 small spinelets, a narrower, keeled, inter- 

 radial plate ; second ambulacral ossicle more than half as 

 long as the first, measured on the summit of the ridge ; 

 furrow spinelet absent beyond the proximal 3 to 14 adambu- 

 lacral plates. 



Type-locality. — 'Albatross' station 4427, off Point San 

 Pedro, Santa Cruz Island, California, 447 to 510 fathoms, 

 black mud. 



Genus Stegnobrisinga, Fisher. 



Stegnobrisinga, Fislier (subgenus), New East Indian Starfishes, Proc. 

 Biological Soc. AVashiugtou, vol. xxix. p. 33 (Feb. 24, 1916). Type, 

 Brisinga {Stegnobrisinga) 2}lcicoder)na, Fisher. 



Diagnosis. — As given in foregoing synopsis. 



The numerous prominent costse will at once separate this 

 genus from Freyetla and Freyellidea. The genus Astrolirus 

 differs in having the first adambulacral plates and first 

 marginal plates arranged as in Brisingella, and in having 

 slenderer adambulacral plates, which, proximally, are not 

 higher than long. 



Brisinga gracilis, Koehler, may be a Stegnobrisinga, but 

 certain necessary anatomical details are not yet known — for 

 example, the number of gonads. 



Astrolirus, gen. no v. 



Diagnosis. — As given in foregoing synopsis. 



The type, Brisinga panamensis, Ludwig, is the only species 

 known. The genus has much the same relation to Stegno- 

 brisinga that Brisingella bears to Brisinga, with the exception 

 of the gonads, which are two to each ray in Stegnobrisinga, 

 and two, or as many as four in very large examples, in 

 Astrolirus. 



Genus Fretella, Perrier, restricted. 



Freyella, Perrier, Ann. sci. nat., Zool. vol. six. art. 8, 1885, p. -5. Type, 

 Freyella spinosa, Perrier, first species. 



Diagnosis. — As given in foregoing synopsis. 

 This group includes those species of the old genus Freyella 

 in which the gonads are numerous and arranged in series 



