150 THE VOYAGE OF H.M.S. CHALLENGER. 



First radial very short ; the second longer and trapezoidal, somewhat incised by the 

 rhombic axillary and forming with it a slight prominence. Axillary as wide as or wider 

 than long, with a fairly open distal angle. 



Ten arms, of some two hundred smooth joints. First brachial rather deeply incised, 

 with a short inner and much longer outer edge ; the second irregularly quadrate, and 

 the six following joints more oblong or obliquely quadrate, with the pinnule on the 

 shorter side. The first three joints above the third syzygy are sometimes nearly 

 triangular and as wide as long, but the following ones are distinctly quadrate and 

 gradually become longer than wide ; the terminal joints somewhat elongated. Syzygies 

 in the third and eighth brachials and then at intervals of two to four joints. 



The first two pinnules long and flagellate, composed of numerous short joints, the 

 basal ones wide and slightly carinate, sometimes with dorsal processes, and the later 

 joints serrate. The third pinnule little more than half as long as the second, with much 

 fewer joints, the basal ones stouter, and the remainder mostly much longer than wide. 

 The following pinnules more massive, with square joints which gradually become 

 elongated. The two lower joints of the distal pinnules flattened and trapezoidal in some 

 forms, but only slightly modified in others. 



Ambulacra not plated, but the disk sometimes bears a number of small calcareous 

 granules. 



Colour in spirit, — white or brownish-white. 



Disk 15 mm.; spread may reach 30 cm. 



Localities. — H.M.S. Challenger, Station 48, May 8, 1873; on the Le Have Bank; 

 lat. 43° 4' N., long. 64° 5' W.; 51 fathoms ; rock. Several specimens. 



H.M.S. "Valorous," Station 6, August 10, 1875 ; Davis Strait ; lat. 64° 5' N., long. 

 56° 47' W.; 410 fathoms ; sand and mud ; bottom temperature, 34° - 6 F. One specimen. 



H.M.S. "Alert," 1875; Franklin-Pierce Bay (in Smith's Sound); lat. 79° 25' N.; 

 and Discovery Bay (in Eobeson Channel), lat. 81° 41' N.; 25 fathoms ; hard bottom. 



H.M.S. "Triton," 1882, Station 4; lat, 60° 22' 40" N. and 60° 31' 15" N., long. 

 8° 21' W. and 8° 14' W.; 327 to 430 fathoms; stones, mud; bottom temperature, 31° "5 

 to 30° F. 



Station 6; lat. 69° 8' 0" N., long. 7° 26' 30" W.; 466 fathoms; stones; bottom 

 temperature, 29 c, 5 F. 



Other Localities. — Barents Sea ("Tegetthoff" and " Willem Barents"); Kara Sea 

 ("Varna") ; Jan May en (Fischer). 



Remarks. — This species has a curious history and has caused me no little trouble. 

 I have no doubt that it was dredged by the " Porcupine" in 1869 in the cold area of 

 the Fseroe Channel, together with Antedon eschrichti, which was met with in compara- 

 tive abundance ; but it is not now to be found among the remains of the " Porcupine " 



