236 ECHINODEIIMA OF THE INDIAN MuSEUM, PART VII. 



but with difficulty separable from the general surface of the centrodorsal and 

 radials ; radials even with the edge of the centrodorsal in the median line, but ex- 

 tending up in the angles of the calyx and entirely separating the bases of the 

 IBr, ; IBr, oblong, slightly over twice as broad as long, evenly roimded dorsally 

 and laterally ; TBr, broadly pentagonal, about as long as broad, the lateral 

 edges not quite so long as those of the IBr, , convex, the lateral angles somewhat 

 produced outward. 



Ten arras, all broken utf at the base in the specimens at hand; first 

 brachial slightly wedge-shaped, about twice as broad as its exterior length, entirely 

 free interiorly; second brachial considerably larger, approximately oblong, not 

 quite so long as broad; third and fourtli brachials (syzygial pair) not quite 

 so long as broad: the remainder of the arms, and the pinnules, so far as can be 

 judged from the fragments, are similar to those in other species of the genus. 

 The synarthriaj tubercles are very slightly marked. 



The colour in spirits is brownish white, the perisome brown. 



hoc ALiTiss.— Duncan Passage. Andaman Islands (11° 31' 40" N. lat., 92"" 46' 

 40" E. long.) ; 188-220 fathoms. (Type Locality). -Two broken specimens. 



Near Interview Island, Andamans (13° 27' 00" N. lat., 93° 00' 00" E. long.) ; 

 405 fathoms; bottom temperature 48° Fahr. ; green mud.— One specimen. 



Gulf of Martahan (14° .54' 30" X. lat., 96° 00' 00" E. long.) ; "6 fathoms" ; 

 soft )n.ud. — One broken specimen. 



PSATHYROMETRA PARVA. 

 Psathi/roviKtru parva 1911. A. H. Clark, Proc. U. S. Nat. Mus., vol. 39, p. 562. 

 Habitat. -Philippine Islands. 

 Depth. — 422 fathoms. 



PSATHYROMETRA GRACILLIMA. 



Psitlhi/rometra (irariUima 1909. .\. H. O.ark, Proc. Biol. Soc. Washington, 



vol. 22, p. 149. 



Description. — This species is even smaller and more delicate than Ps. mira 

 and Ps. parva. 



Centrodorsal sharply conical, 4 mm. broad at the base and 25 mm. high, 

 separated intb five radial areas by live interradial furrows which are somewhat 

 broader than the adjacent cirrus sockets ; eight to ten well separated cirrus 

 sockets in each radial area, Mrranged approximately in four columns, though 

 apparently more or less irregular. 



Cirri XL -L, about 25, 35 nun. Imio;, slender, smooth, and delicate. 



The ten arms which, excc)i( for their slendeiiiess, resemble those of related 

 species, are about 100 mm. long. 



The colour in life is a " pale earthy brown." 



