EEPOET ON THE CRINOIDEA. 171 



the lowest of which are stouter than in the first pair. The following pinnules similar 

 in character and of gradually increasing length, with fusiform genital glands. The 

 basal joints of the distal pinnules are quite short, with their apposed edges incurved, and 

 the following joints are greatly elongated. Disk naked ; the brachial ambulacra some- 

 times provided with delicate calcareous rods, which alternate with the numerous sacculi. 



Colour in spirit, — white. 



Disk reaching 7 mm.; spread may be 8 cm. 



Localities-. — H.M.S. "Porcupine," 1869, Station 51 ; lat. 60° 6' N., long. 8° 14' W.; 

 440 fathoms ; bottom temperature, 42° F. One specimen. 



Station 54 ; lat. 59° 56' N., long. 6° 27' W. ; 363 fathoms ; bottom temperature 

 31°"4 F. One specimen. 



Station 55; lat. 60° 4' N., long. 6° 19' W. ; 605 fathoms; bottom temperature, 

 29 0, 8 F. Two specimens. 



Station 74; lat. 60° 39' N, long. 3° 9' W. ; 203 fathoms; bottom temperature, 

 47°'6 F. Three specimens. 



Cruise of 1870, Station 17a; lat 39° 39' N., long. 9° 39' W.; 740 fathoms; bottom 

 temperature, 49° "3 F. One specimen. 



H.M.S. "Triton," 1882; Station 2; lat, 59° 37' 30" N., long. 6° 19' W. ; 530 

 fathoms ; mud ; bottom temperature, 46 c, 2 F. Five mutilated specimens. 



Station 5; lat. 60° 11' 45" N. and 60° 20' 15" N., long. 8° 15' W. and 8° 8' W.; 

 433 to 285 fathoms ; hard ground, stones ; bottom temperature, 43°"5 to 40°*8 F. Two 

 specimens, with Myzostoma carpenteri. 



Other Localities. — The Shetlands ; Scandinavia; Kara Sea; Barents Sea; West 

 Atlantic, off the American coast from Nova Scotia to New Jersey. 



History. — This species was separated by Eetzius 1 in 1783 from the Asterias 

 pectinata of Linnaeus, the type of which was an Actinometra from the Indian Ocean, 

 but Linnaeus also referred to it the AeK<xKvr]iJLo<; rosacea and Acca»c^/Ao? barbata of 

 Linck. These seem to be the British and Mediterranean varieties respectively of the 

 somewhat protean type which is now known as Antedon rosacea. In fact Linnaeus's 

 description of Asterias pectinata would apply equally well to almost every ten-armed 

 Comatula ; and it was remarked by Eetzius that " the definition of the species is such 

 that it includes two species, namely, pectinata and tenella." He described the latter 

 form as being more debcate than Asterias pectinata, and as having the " bases brachiorum 

 duplicatorum multo longiores." 2 This is a distinction of almost generic value between 

 Antedon and Actinometra, in which latter genus the relative length of the radials is quite 

 small ; and Retzius pointed out further differences in the shape of the arm -joints between 



1 Anmarkningar vid Asteri:e Genus, K. Svensk. Vetensh. Akad. Handl., 1783, t. iv. p. 241. 

 " Dissertatio, sistens Species Cognitas Asteriaruin, Lundie, 1805, p. 33. 



