A. H. CTjARK : THE CBINOIDS OF THE INDIAN OCEAN. 185 



Genus PEGTINOMETRA, nov. 



Genotype. — Anted.on flavopurpurea A. H. Clark, 1907. 



Diagnosis. — -A genus of Calometridae in which the IIBr series are 2 ; the cirri 

 are of moderate lengtii, about one third as long as the arms, composed of short 

 segments, of which the longest are rarely longer than broad; the radials are 

 seldom produced interradially, rarely separating the bases of the IBr, ; the 

 elements of the IBr series, and usually also of the IIBr series and the first two 

 brachials, have strong, more or less irregular lateral processes; the brachials are 

 short so that the pinnules, which are not especially slender, appear closely set. 



PEGTINOMETRA MAGNIFIGA. 



Calometra magnifica 1909. A. H. Clark, Proc. Biol. Soc. Washington, vol. 22, 



p. 77. 



Description. — Centrodorsal hemispherical, the bare polar area convex, 

 2 mm. in diameter ; cirrus sockets arranged in two or three closely crowded 

 irregular marginal rows. 



Cirri XX, 41-48, 40 mm. long; first segment short, the next two about twice 

 as broad as long, the following gradually increasing in length to the fifth or seventh, 

 which is about one third broader than long ; following segments similar to almost 

 the middle of the cirrus, at which point they begin to decrease gradually in length, 

 being twice as broad as long in the terminal portion ; at about the eighth segment 

 the median portion of the distal dorsal edge begins to project in a small A- 

 shaped spine ; this very slowly increases distally, the whole dorsal surface of the 

 segment becoming rounded carinate and rising at the same time until in the terminal 

 third the cirrus segments bear broad spatulate carinate processes wliich are equal 

 in height to about one third their diameter ; opiDOsing spine triangular, similar in 

 shape and size to the spine on the preceding segment, blunt, the apex terminal, 

 ai'ising from the distal two thirds of the penultimate segment, about equal to one 

 half of the lateral diameter of the penultimate segment in height ; terminal claw 

 conical, equal in length to the penultimate segment, stout, slightly curved. 



Disk completely covered with a pavement of rather small rounded plates, 

 those in the angles of the calyx between the division series bearing conical pro- 

 cesses in their centres ; this calcareous covering is not closely united to the perisome 

 beneath except along the ambulacra, but draws away from it in drying ; ambulacra 

 with side and covering plates highly developed. 



Ends of the basal rays visible as small, though prominent, tubercles in tiie 

 angles of the calyx: radials even with the edge of the centrodorsal, but over the 

 ends of the basal rays extending upward in a narrow slightly wedge-shaped (base 

 upward) process which terminates distally in a spatulate tip between the lateral 

 edges of the IBr.^ ; IBr, short, slightly trapezoidal, not in contact basally, about 

 four times as broad as long, rather strongly convex dorsally, with a rather promi- 



