229 



12. Psathyrometra inusitata A. H. Clark. 



A. H. CLARK. Records of the Indian Museum, vol. 7, 1912, part 3, N" 26, p. 270 (nomen 

 nudum ; 7 miles S.E. by S. from Ross Island ; 265 fathoms). 

 - Notes from the Leyden Museum, vol. 34, 1912, p. 141 [Psathyrometra inusitata). 



Stat. 38. 7°35'.4S., ii7°28'.6E. Flores Sea. 521 Metres. 1 Ex. 



Stat. 45. 7°24'S., n8°i5'.2E. Flores Sea. 794 Metres. 1 Ex. 



Stat. 178. 2°4o'S., 128 37'. 5 E. Ceram Sea. 835 Metres. 1 Ex. 



Stat. 314. 7 36' S., 117° 30'. 8 E. Flores Sea. 694 Metres. 1 Ex. 



Stat. 316. 7°i9'.4S., u6°49'.5E. Flores Sea. 538 Metres. 2 Ex. 



The centrodorsal is small and conical, the sides slightly, if at all, convex; the basal 

 diameter is 3.2 mm., the distance from the apex to the interradial border 2.4 mm.; five very 

 narrow bare areas divide the sides of the centrodorsal into five radial areas ; these at the base 

 are rarely half as broad as the adjacent cirrus sockets, and they are more or less èncroached 

 upon by the cirrus sockets on either side so that their course is usually more or less zigzag 

 or irregular; they are scarcely to be recognized otherwise than that the outer columns of 

 cirrus sockets in each radial area are slightly separated from the outer columns in the next 

 area, whereas within each area all the columns are closely crowded. 



Each radial area has three columns of cirrus sockets, the two outer of four each, the 

 median of two only; the sockets are very closely crowded, the two outer columns coming into 

 apposition just beyond the median; at the dorsal pole there are a number of pits representing 

 obsolete cirrus sockets, some of which are situated in the interradial furrows; their arrangement 

 appears to be in alternating rows instead of in columns. 



No basal rays are visible. 



The radials are even with the edge of the centrodorsal, but extend slightly upward in 

 the angles of the calyx, where their tips are slightly separated. The \¥>x x are short, proximally 

 nearly four times as broad as long in the median line, but 

 decreasing in width distally where they are only about three 

 times as broad as long in the median line; they are widely 

 separated from their neighbors; the IBr„ (axillaries) are rhombic, 

 half again as broad as long, with the anterior angle produced; 

 the lateral angles extend far beyond the distal lateral angles ■ 

 of the IBrj and meet those of their neighbors, forming large 

 water pores; the synarthrial tubercle is only slightly indicated. 



The first brachial is three times as long exteriorly as 

 interiorly, half again as broad basally as the exterior length; 



■" o J ° Fig. 13. 



the inner edges are entirely free and make approximately a Lateral view of the centrodorsal eind arm 



. . bases of a specimen of Psathyrometra inusitata 



right angle with those of the adjacent first brachials ; the from near the PosüUon Islands . Enlarged , 

 outer sides are in apposition with the outer sides of the first (Courtesy of the u. s. National Museum), 

 brachials on the adjacent rays. The second brachial is irregularly quadrate, the two of each 

 arm pair in contact interiorly so that a water pore is formed similar to that between the 

 ossicles of the IBr series. The first syzygial pair (formed of the third and fourth brachials is 



