A MONOGRAPH OF THE EXISTING CRINOIDS 561 



Abnormal specimens. In the individual from off Hong Kong the right anterior 

 ray is very curiously developed. 



On the right IIBr series (as viewed dorsally) the inner IIIBr series terminates 

 in a doubled axillary 2 axillaries side by side which forms an epizygal superposed 

 upon the single hypozygal of the syzygial pair. Each half of this doubled axillary 

 gives off 2 arms so that 4 arms arise from this single division series. Ventrally the 

 ambulacral groove on reaching this axillary divides into 3 parts, 1 of which runs to 

 the left (right as viewed dorsally) and soon divides, supplying 2 arms, while the 

 other 2 run undivided to the 2 remaining arms. 



The left IIBr series arising from this IBr series is undivided. It consists of only 

 9 brachials of which the last bears a single terminal pinnule of large size. The struc- 

 ture tapers regularly from the axillary to the base of the terminal pinnule. The third 

 and fourth brachials are united by syzygy so that this arm stump bears 7 pinnules in 

 all, 6 lateral on alternate sides of the arm and 1 terminal. 



In a specimen from Mortensen's station 10, Gisle"n found a case of distal arm 

 branching. The right posterior ray bears 2 IIBr 4 (3 + 4) series. The inner deriva- 

 tive from each is unbranched. The outer derivative of that to the right carries ex- 

 ternally a IIIBr 4 (3+4) series bearing 2 undivided arms. The outer derivative of 

 that to the left forks on the eighth brachial, which is the epizygal of the third syzygial 

 pair, syzygies occurring between brachials 3 + 4, 5 + 6, and 7 + 8. Doctor Gisle"n in- 

 terprets this as a case of an inner pinnule that has developed into an arm. But he 

 says that here we get a picture of the repetition, as far as possible normal, in more 

 distal parts of the arm of the proximal arm ramification and its distribution of non- 

 muscular articulations. 



In another specimen from Mortensen's station 10, PI is lacking on an inner arm 

 arising from a IIBr series. 



Another specimen from the same station has 1 of the IIIBr series 2. 



A fourth example from the same station has 1 of the IIBr series 1, 2 of them 2, 

 and the remaining six 4 (3 + 4). 



Remarks. While in the great majority of cases this species has a very charac- 

 teristic appearance and is readily distinguishable from all other comasterids, it seems 

 to intergrade to a certain extent both with C. japonica and with C. solaster. 



It is, perhaps, most easily confused with C. trichoptera which, however, has a 

 discoidal centrodorsal with a broad flat dorsal pole and much more slender cirri. 



Localities. Eight miles outside Hong Kong Harbor (lat. 22 12' N., long. 114 

 15' E.); 25 meters; Captain Suensson, November 16, 1911 [A. H. Clark, 1913; Gislen, 

 1927] (1, C. M.). 



Northeast of Swatow, China (lat. 23 15' N., long. 117 40' E.); Capt, H. 

 Christiansen, July 26, 1912 (3). 



South of the Goto Islands, Korean Straits (lat. 32 15' N., long. 128 20' E.); 

 183 meters; Capt. H. Christiansen, April 17, 1926 (1). 



Between the Goto Islands and Nagasaki (lat. 32 48' N., long. 129 37' E.); 73 

 meters; bottom temperature 11.67 C.; Capt. H. Christiansen, S. S. Nordiske, April 

 23, 1912 (5). 



