504 MB. P, H. CAEPENTEB 01>i NEW 



equality in length of the smootli lower pinnules on the outside of 

 the arm distinguish this species from any hitherto described. 



3. Antedon J5QUIPINNA, n. sp. 



J)escription of an Individual. — Centrodorsal discoidal, bearing 

 about forty cirri in a single or partially double marginal row, which 

 leaves the flat dorsal surface free. Cirri of 24-28 tolerably uni- 

 form, smooth, thick joints, of which the sixth is about square, while 

 those immediately following it may be a trifle longer than broad ; 

 the penultimate has a small blunt spine, a trace of which is some= 

 times visible on the preceding joint. 



First radials not visible ; second short and wide, nearly oblong, 

 slightly united laterally. Axillaries less than twice their length, 

 pentagonal, with wide distal angles. 



43 arms of 160 smooth joints, the rays dividing three or rarely 

 four times. Each division of two joints, the first closely united 

 to their fellows and the axillary not a syzygy. First brachials 

 almost rhomboidal, relatively long and narrow and closely united 

 to their fellows. Second joints much shorter and nearly oblong, 

 slightly longer on the outer than on the inner side. Third (a 

 syzygy) and the next four joints transversely oblong, with traces 

 of forward and backward projections alternately on opposite sides. 

 The following ones longer, though still short and sharply wedge- 

 shaped, considerably wider than long; becoming blunter towards 

 the middle of the arms and squarer towards the ends. 



First syzygy on the third brachial, and the next between 9 and 

 20, usually about 16 ; after which the syzygial interval is 6-12, 

 usually 8 or 9, joints. 



First pair of pinnules, on second and third brachials, short, 

 slender, and tolerably equal, of about 20 longish joints. The next 

 pair twice their length (13 mm.), much stouter, and rather stiff. 

 The next pinnule (on 6th brachial) somewhat smaller than the 

 first one, and the next four continue to decrease. The remaining 

 pinnules gradually increase in length, becoming slender and deli- 

 cate in the outer parts of the arms, but not longer than the 

 second pair. 



Disk naked and somewhat incised, 20 mm. in diameter, and 

 coloured dark grey. Skeleton an alternation of purplish red and 

 white, with alternating double rows of dark spots on the white 

 parts. 



Brachial ambulacra close down between the muscles; those 

 of the pinnules more fleshy, with closely set sacculi. 



