512 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



Type-locality. — Station 5491, between Leyte and Mindanao, 736 

 fathoms, green mud, coral, bottom temperature 52.3° F. ; 1 speci- 

 men. 



Distribution. — Philippine Islands, 604 to 772 fathoms. 



Specimens examined. — Besides the type, 11, from the following 

 stations : 



Station 5215, east of Masbate, 604 fathoms, green mud ; 1 specimen. 



Station 5487, between Leyte and Mindanao, 732 fathoms, green 

 mud, bottom temperature 52.3° F. ; 3 specimens. 



Station 5488, same locality, 772 fathoms, green mud, bottom tem- 

 perature 52.3° F. ; 3 specimens. 



Station 5494, same locality, 678 fathoms, green mud and sand, bot- 

 tom temperature 53.3° F. ; 3 specimens. 



Station 5515, Iligan Bay, north coast Mindanao, " about 700 

 fathoms." 



Remarks. — There are 2 multicostate forms described by Alcock from 



the Indian region, B. andamanica ( —-. + -^ )' ^^^ ^- 9'^'^''^^^ ( TTZTi "^ ^ )' 



having practically the same adambulacral formula as the present 

 species, although the description of B. gunnii does not state the lo- 

 cation of the smaller actinal spine. The formula might be i -^ + / j- 



From B. andamanica., this species differs in having more closely 

 crowded costae, with strongly, not feebly developed plates, in having 

 a longer costal region, in lacking well-developed bands of pedicel- 

 lariae between the costae, in having fewer (12 or 13, not 15) less 

 deciduous rays, and a relatively longer minor subambulacral spine 

 (the adoral). B. gwnnii differs in having more numerous rays, much 

 thinnor disk, which has a downy appearance (spiny in tracJiydisca) ^ 

 only 20-30 ridges, especially prominent laterally but becoming in- 

 conspicuous or obsolete abactinally, intercostal bands of pedicellariae, 

 a much shorter major subambulacral spine (/ of formula), a slightly 

 shorter minor subambulacral spine, and mouth plates composed of 2 

 incompletely fused abambulacrals, leaving a " ligamentous symphysis 

 between." 



Genus CRATEROBRISIN GA Fisher. 



CrateroWisinga Fisher (subgenus), 1916&, p. 33; 1917f, p. 624, Type, B. 

 panopla Fisher. 



Diagnosis. — Differing from typical Brisinga (which it resembles 

 in appearance and in the possession of serial gonads, and of closely 

 opposed first adambulacral and first marginal plates of adjacent 

 rays) in having proximally 2 subambulacral spines of conspicuous 

 size, the larger of which (and also sometimes the smaller) has an 

 enlarged, modified, capitate, often truncate tip. Costae usually 



