CLARK: JAPANESE AND EAST INDIAN ECHINODERMS. 287 



Oral spines rather slender, all united by membrane ; superoral spine not 

 stout and triangular-pointed ; actino-lateral spines much longer near mid- 

 dle of ray than near tip pulvillus. 



Oral spines not united by membrane; first two (innermost) very flat and 

 truncate ; superoral spine very stout and triangular-pointed ; actino-lateral 

 spines of approximately equal length except at very tip of ray . obesus. 

 Abactinal surface not much elevated and not at all warty. 



Oral spines 3, united by membrane ; R = 1.5 r± multispinus. 



Oral spines 6 or 7, not united by membrane ; R = 1.7 r± . . reticulatus. 

 Adambulacral armature of 3-5 (rarely 0) spines. 

 Oral spines 6. 



2 innermost spines long, 4 lateral short, each group united by a web ; thus 

 4 groups to each mouth angle ; adambulacral spines usually 4 ; no spir- 



acula alveolatus. 



Oral spines of each mouth angle all (12) united by a common membrane 

 into a single group ; adambulacral spines usually 5 ; spiracula very 



abundant multiporus. 



Oral spines 3-5. 

 Oral spines not united by a web. 



Adambulacral spines short, scarcely projecting beyond web . . stellifer. 

 Adambulacral spines slender, projecting far beyond web . . . danae. 

 Oral spines united together by a web. 

 Adambulacral spines usually 3, sometimes 4, short, scarcely projecting 



beyond web rugatus. 



Adambulacral spines 3-5, usually 4, projecting far beyond web. 

 R = 1.75 r± ; dorsal membrane thin, evidently reticulated 



semireticulatus. 

 R = 1.4 r± ; dorsal membrane thick, not at all reticulate . . ingoufi. 



Echinaster eridanella. 

 Midler & Troschel, 1842. Sys. Ast., p. 24. 



1 specimen, with six rays, 110 mm. in diameter. Very deep crimson-red in 

 life. Manokwari, New Guinea. — 1 specimen, with six rays, 60 mm, in diameter. 

 Red in life. Makassar, South Celebes. Barbour collection. 



Asterias rollestoni. 

 Bell, 1881. Proc. Zool. Soc. London, p. 514. 



1 young specimen, 50 mm. in diameter. Nearly white, more or less mottled 

 with deep gray abactinally. Tokyo Bay, Japan, five fathoms. Owston collection. 



Although this specimen does not correspond perfectly to either Bell's or 

 Doderlein's (Zool. Anz., 25, p. 333) description, 1 think there can be little 

 doubt that it belongs to this species. 



