STARFISHES OF THE PHILIPPINE SEAS. 535 



different in form ; articular surface of proximal ambulacral os- 

 sicles larger, the pair being 1.5 times higher than broad ; rays 



-|^4 Brisingenes anchista (Fisher). 



e\ Costae opposite alternate ambulacral plates, heuce well spaced; 

 with conspicuous intercostal bands of pedicellariae. 

 f Ravs 15 : costae 30 to 35 ; disk medium, some of its plates with 



, , , i+l+I o+l±I, 



more than 1 spinelet ; adambulacral formula — ~ — or - , 



suboral spine rather small and delicate; gonads serial, more 

 than 2 to each ray; proximal subambulacral spines slightly 



modified, blunt Craterobrisinga cvennamii (Fisher). 



f Rays 16, with 25 prominent, complete, costae and 1 to 3, usually 3, 

 conspicuous intercostal bands of pedicellariae; disk medium- 

 sized with abruptly rounded (not beveled) margin; actinostome 

 relatively very large ; 1 suboral spine to each mouth plate and 

 with an angle at base so that it is directed into actinostome; 

 disk plates with solitary spinelets only ; lateral spines equal in 

 length to 5 or 6 consecutive adambulacral plates ; adambulacral 



armature V^ or ^4j^; gonads 2 to each ray. 



Astrostephane mohiccana (Fisher). 

 f. Rays 11, with about 20 complete, prominent costae and 1 complete, 

 and lor 2 incomplete, bands of intercostal pedicellariae; disk, 

 decidedly small with a beveled margin ; actinostome relatively 

 small ; 2 large suboral spines to each mouth plate ; disk plates 

 with 1, 2, and 3 small spinelets in about equal numbers ; lateral 

 spines equal in length to 7 or S consecutive adambulacral plates; 



i+I 

 ajfibulacral armature v-^-^; gonads 2 to each ray. 



Astrostephane acanthogenys (Fisher). 



d' Rays 10 or less; rays very fragile; disk small; suboral spines small; 



first pair of adambulacral plates of interbrachium not joined by 



lateral face; first pair of marginal plates joined by adoral end of 



plates only ; gonads 2 to each ray. 



e\ Rays 10; costae rather variable, usually 24 to 28 complete ones and 



a varying number of intermediate incomplete ridges in the median 



area ;' marginal mouth spinelets 4, 3 on the actinostomial margin; 



suboral spines 2, small Brisingclla fragilis (Fisher). 



e». Rays 7; costae few— less than 15; marginal oral spinelets 2 on 

 actinostomial margin; 1 small suboral spine; a few isolated 

 spicules in the intercostal integument. 



BriHingella armillata (Sladen). 



b' Tegumentary prickles in abactinal membrane of ray. 

 V Rays 13 to 14 ; base of ray for some distance provided with conspicuous 

 prickles springing from irregular roundish plates, which do not form 

 definite costae; intercostal plates beyond this basal area usually un- 

 armed ; costae 18 to 24, the alternate ones complete, and the first at 

 a distance about equal to r from the base of ray. 



Stegnobrisinga gracilis (Koehler). 



(f Rays 7, costae few, less than 15 ; tegumentary prickles few. 



BrisingeUa armillata (Sladen). 

 ' Intercostal integument of proximal part of ray thin, with or without rudi- 

 mentary spaced plates bearing tegumentary prickles ; 1 or 2 subambulacral 



