376 HAWAIIAxN AND OTHER PACIFIC ECHINI. 



PODOPHORA. 



L. Agassiz, 1840. Cat. Syst. Ectyp. Echinod., p. 19. 

 Type-species, Echinomelra atrata de Blain\dlle, 1830. Diet. Sci. Nat., LX, p. 206. 



As this genus and the following have been so fully discussed in a recent 

 Monograph (A. Agassiz, 1908, Mem. M. C. Z., XXXIX), it would be quite 

 superfluous to go into any details here. There are two distinct species in 

 the genus, one of which (atrata) is wide spread in the Indo-Pacific region, 

 ranging from Zanzibar to Hawaii, while the other (pedifera) is confined, so far as 

 known, to the southeastern Pacific. 



The two species are readily distinguished from each other as follows: — 



Color abactinally, usually deep purple, rarely greeni-sh; marginal primary spines with 

 rounded, .sometimes swollen ends, not forming a close-set, even margin; actinal 

 p(,'taliferous areas of ambulacra moderately developed, not abruptly constricting 

 the interambulacral spaces; pore-pairs at ambifus in arcs of 9 or 10 airala. 



Color, abactinally olive-green; marginal primary spines with flattened, chisel-like tips, 

 forming a close-set, even margin; actinal petaliferous ambulacral areas greatly 

 developed, abruptly constricting the interambulacral spaces; pore-pairs at ambi- 

 tus in arcs of 10-12 pedifera. 



Podophora atrata Agass. 



Echinus atratus Linn6, 1758. Syst. Nat., ed. 10, p. 655. 



Podophora atrata L. .Vga-ssiz, 1840. Cat. Syst. Ectyp. Echinod., p. 19. 



"Colobocentrotus Quoyi Brandt," A Agassiz and Clark, 1907. Bull. M. C. Z., L, p. 240. 



This appears to be one of the common and characteristic sea-urchins of the 

 Hawaiian Islands, and was found by the "Albatross" in considerable numbers 

 particularly at Puako Bay, Hawaii. A collector's note with a jar of specimens 

 from this j)lace reads as follows: — 



"( 'omnion on rocks along shore. Live in little depressions, the border spines 

 acting as the o(lg(^ of a sucking di.sk. Dorsal surface very deep Indian jnirple 

 or i)rune-pur|)l(^ when in the water. By reflected light, out of water, almost 

 black. Underside of big spines, mauve. Circumoral membrane and memlirane 

 between clunip.s of small spines and tubefeet, orange-red. Small spines and 

 tube-feet, light brownish, occasionally red or purple." 



Necker Island, Hawaiian Islands. 



Kamalino Bay, Niihau. 11. T. 



Napili Harbor, Maui, H. I., ".Mbatross" St. 3881. 



Napiii, Maui, II. I. 



