298 BULLETIN: MUSEUM OF COMPAKATIVE ZOOLOGY. 



Ophiarachna incrassata. 



Ophiura incrassata Lamarck, 1816. Anim. s. Vert., 2, p. 542. 

 Ophiarachna incrassata Miiller & Troschel, 1842. Sys. Ast., p. 104. 



1 specimen. Diameter of disc, 24 mm. Color : disc greenish, centre, and 

 areas over radial shields, light brownish {not in marked contrast) spotted with 

 yellow; arms reddish buff; arm-spines light yellow, each with from two to four 

 rings of brownish red ; oral shields reddish buff, each with a round yellow spot. 

 Ainboina. Barbour collection. 



This very handsome specimen, though dry, is nearly perfect. It is of interest 

 because the color agrees fairly well with Miiller and TroschePs original descrip- 

 tion, whereas the " Siboga " specimens seem to have been deep green ; at least 

 Koehler says (1905, Oph. "Siboga," pt. 2, p. 65) that Herklot's (1868) colored 

 figure, which is very rich green, variegated on the disc with whitish, is " sufnsam- 

 ment exact." 



Ophiothrix longipeda. 



Ophiura longipeda Laruark, 1816. Anim. s. Vert., 2, p. 544. 

 Ophiothrix longipeda Miiller & Troschel, 1842. Sys. Ast., p. 113. 



2 specimens. Diameter of disc, 15 mm. Color purple variegated with whit- 

 ish; spines and spiuelets white or nearly colorless. Amboina. — 2 specimens. 

 Diameter of disc 12 mm. Color similar to those from Amboina but lighter. So- 

 rong, New Guinea. Barbour collection. 



Ophiocreas papillatus, sp. nov. 



Diameter of disc, 15 mm.; length of arm, about 250 mm. ; width of arm at 

 base, 4 mm. ; height of arm at base, 4 mm. Disc flattened, not higher than 

 arms, concave at centre, covered by a thin skin, which is thickly dotted in radial 

 areas and near margin with minute roundish calcareous granules ; of these there 

 are, where thickest, about 75 to a square millimeter. Radial shields long, narrow, 

 and flattened especially towards centre, where they approximately meet ; no two 

 are elsewhere in contact. They appear to be made up of several thin, flat, super- 

 posed, overlapping plates. Extending from outer end of radial shield at right 

 angles to it, on margin of disc, is a small but very distinct plate, about a milli- 

 meter long ; it appears to limit upper border of genital slit. Arms approximately 

 cylindrical but flattened ventrally, tapering very gradually, not at all enlarged at 

 base. No upper arm-plates. Skin at base of arm thickly sprinkled with minute 

 calcareous granules like those on disc. Genital plates nearly as large, but not so 

 long, as radial shields; genital slits 4 mm. long, nearly vertical, and parallel. 

 Oral shield wholly invisible. Adoral plates large but indistinctly outlined. Oral 

 plates two, projecting and rather conspicuous. Oral papillae small, rounded, of 

 unequal size, very variable, from five to nine on each side of mouth-slit, situated 



