Clark — Six New East I ml inn Crinoids. 79 



developed excepl for one which i- external by the side of an internal 

 mi Br series. 



Type locality. — "Siboga" station No. 254. 



Pachylometra fragilis sp. nov. 



The centrodorsal is low, flattened hemispherical, 7 nun. in basal diam- 

 eter and 3 mm. high; the cirrus sockets are closely crowded, in two or 

 three irregular rows and approximately fifteen columns, three in each 

 radial area: the cirrus sockets touch the proximal border of the centro- 

 dorsal. 



The cirri are about xxx, L7-18, 30 nun. to 35 mm. long, moderately 

 -lender; the first four segments are short, the fifth is half again as long 

 as broad; the sixth-eighth are the longest, twice as long as broad; the 

 following slowly decrease in length becoming about as long as broad dis- 

 tallyand then increase again so that the penultimate and antepenultimate 

 are about twice as long as broad; the earlier longer segments have slightly 

 prominent ends, and the shorter distal segments have the distal dorsal 

 margin slightly swollen. 



The subradial clefts are deep, but very narrow; the ends of the basal 

 rays are visible as large and prominent rhombic areas in the angles of the 

 calyx; the radials are very short, strongly curved, with a low broad ob- 

 scure median tubercle; the r B.n are extremely short, band-like, with an 

 obscure low median tubercle; they are produced inward toward the center 

 of the calyx so that their sharply flattened lateral edges almost meet, being 

 separated only by a narrowly V-shaped cleft running to the edge of the 

 inner edge of the synarthrial joint face; though the dorsal surface of the 

 segment is well rounded the distance from the central canal to the median 

 part of the dorsal edge is not so great as the distance from the central 

 canal to the inner angle; counting the entire median length of the joint 

 face the broadest portion is found to be scarcely more than one third of 

 the distance from the dorsal edge to the innerangle; the ossicle is sharply 

 "wall-sided" from its widest point inward; the axillaries are low, 

 rhombic, with the lateral angles truncated so that the lateral edges are 

 about as long as the lateral edges of the iBn, twice as broad as long; 

 there is an obscure well rounded median carination; the distal angle is 

 produced, but broad; the dorsal surface is rather strongly convex; the 

 lower portions of the axillaries are strongly produced inward so that, like 

 the i Bri, the inner sides are reduced almost to apices which almost meet 

 the similar inner ends of the other axillaries; from this central point the 

 inner face of the axillaries slopes away almost horizontally so that the 

 inner lace- of the axillaries, together with the division series, form the 

 platform upon which the visceral mass rests; the sides of the inner half 

 of the axillaries are sharply "wall-sided"; the nBr series are similar 

 to thi' i I >r series, hut rapidly decrease in dorsoventral width; they are 

 sharply flattened laterally for somewhat more than their inner half; the 

 first two brachials are flattened laterally for their entire inner side and the 

 third and fourth are flattened on the inner portion of the inner side. 



