158 DISCOVERY REPORTS 



broad (Fig. 8 a). The third and fourth are as long as broad. The fifth is shghtly longer 

 than broad. The sixth to eighth are shorter than the fifth, but each is longer than broad. 

 All the remaining segments are slightly broader than long. From the twelfth onwards 

 they are wider distally than proximally and the dorsal edge is rounded but it is not 

 raised into a keel or spine. The opposing spine is strong; it has the shape of an equilateral 

 triangle and arises from the entire dorsal edge of the penultimate segment. The terminal 

 claw is moderately strong and curved. 



The radial is short with a concave distal edge ; its width is six times the length in the 

 midline (Fig. 8 b). The costal is four times as wide as the lateral, greatest, length. It is 

 moderately deeply incised by the axillary. The costals are not in apposition. The axillary 

 is one-and-a-third times as broad as long. The proximal edges are faintly concave, the 

 posterior projection broadly rounded ; the distal edges are deeply concave so that the 

 anterior projection is narrow and pointed. The radials, costals and axillaries are smooth. 



Syzygies are numerous. The positions of the first three are 3 + 4, 9 + 10, 14 + 15; 

 the pairs occur thereafter at intervals of one to three, usually two, brachials. 



The first brachial is short with a longer exterior than interior edge; it is slightly 

 incised by the second. The second is a little broader than long with a broadly rounded 

 posterior projection and a concave distal edge. Both brachials are smooth. The interior 

 edge of the first syzygial pair is considerably longer than the exterior. The brachials 

 between the first and second syzygies are slightly broader than long. The fifth is rect- 

 angular with its interior proximal corner produced backwards. The succeeding brachials 

 are similar, with, alternately, the exterior and interior proximal corners produced back- 

 wards. They gradually change in shape so as to be wedge-like at the second syzygy. 

 Beyond the second syzygy the brachials are triangular, a little longer than broad. 

 Farther out on the arm they become quadrangular, with oblique proximal and distal 

 edges, and more elongate. The distal edges of all the brachials beyond the first syzygy 

 are everted and rough with spines. 



Pi is longer and much more massive than Pg ; P3 is the first genital pinnule. Pj is of 

 14 segments, 4 mm. long, and extends as far as P. (Fig. 8 c). The segments are strong 

 and rounded and a little longer than broad ; their dorsal surfaces and distal edges are 

 rough. P2 is of 10 segments, 3 mm. long; all but the first segment are longer than broad: 

 the fourth and succeeding segments are twice as long as broad. P3 is of 10-12 segments, 

 about 3 mm. long, and has an ambulacral furrow (Fig. 8 d). The first two segments are 

 short. The third to seventh, along which the gonad lies (a testis, for the specimen is a 

 male), are considerably longer. They are slightly expanded. The third is as long as 

 broad. The fourth is as wide but slightly longer. The fifth is not so wide as the fourth; 

 it is longer than broad. The sixth is narrower and about twice as long as broad ; the 

 seventh is more than twice as long as broad. The remainder are narrow and elongated, 

 about three times as long as broad. All the segments have strongly everted and spinous 

 distal edges ; the spines are strongest on the aboral edge of the expanded segments. 



The genital pinnules extend to Pis . They resemble P3 except that the expansion of 

 the segments along which the testis lies gradually lessens; it disappears about P^ 



