308 BULLETIN 82, UNITED STATES NATIONAL MUSEUM VOLUME 1 



more abundant on the southwestern side, and at the entrance to the passages between 

 the islands. The point nearest to Nanaimo at which they have been found is about 

 6 miles away, and about 9 miles from the Station. Most of them have been obtained 

 in water of from 27 to 55 meters in depth. There must be many acres, if not miles, 

 pretty well covered with them. 



In June and July, 1915, Dr. Th. Mortensen found this species to be fairly common 

 near Nanaimo in a place near Ruxton passage at a depth of about 27 to 46 meters. 



He observed this form swimming actively after the usual manner of comatulids. 



Occurrence of the pentacrinoids.- Professor Fraser wrote (1918) that the larvae of 

 this species become attached to the adults, and Dr. Mortensen (1920) from among over 

 200 specimens took 10 pentacrinoids attached to the cirri. 



History. Prof. William E. Ritter in a note published in 1902 first called attention 

 to the existence of comatulids on the west American coast; he had obtained a few speci- 

 mens by dredging off San Diego in about 183 meters (100 fathoms). But many years 

 before, on January 5, 1889 (Sta. 2893) the Albatross had first secured this species among 

 the Santa Barbara Islands, dredging it in abundance on February 8 (Stas. 2952, 2954- 

 2956) and 9 (Sta. 2959) of the same year. On all her subsequent cruises on the west 

 coast she met with this species in local abundance everywhere, but always in fairly 

 deep water. 



Dredging operations carried on at Pacific Grove, near Monterey, had yielded this 

 form, and the myzostomes on some of the specimens secured were described by Prof. 

 Jesse F. McClendon in 1906. 



From the material which had been accumulating in the U.S. National Museum as a 

 result of the \vork of the Albatross, I described in 1907 Antedon perplexa and A. ser- 

 ratissima, both from the coast of Washington. I learned later that Mr. Cloudsley 

 Rutter, the naturalist of the Albatross, at the time of his death had been especially 

 interested hi the crinoids, and had conferred upon this species the MS. name of 

 Antedon asper. 



Professor Ritter now sent me the comatulids which he had dredged off San Diego 

 and recorded in 1902. These did not seem to agree either with my perplexa or with my 

 serratissima. It seemed to me at the time most probable that they represented Hart- 

 laub's tanneri, described from somewhat further south, and under that name I recorded 

 them in 1908, at the same tune mentioning the occurrence of a reduplicated first brachial 

 pair in one of them. 



In 1911 Mr. Dan Brown, of Wrangel, Alaska, while fishing on the southeastern 

 side of Etolin Island, brought up a specimen from a depth of 11 meters, the only one 

 that has ever been obtained other than by dredging. 



The late Prof. C. McLean Fraser found comatulids to be abundant in the vicinity 

 of the Biological Station at Nanaimo, when he was director, and was kind enough to 

 send me some of them with notes on their occurrence in that region, which notes I 

 published hi 1915. He brought out some additional information and noted the occur- 

 rence of the pentacrinoid young in 1918. 



After a reexamination of all the material available, I remarked in 1918 that ser- 

 ratissima is probably only a spinous form of perplexa; but I included with the latter the 

 specimens which had been recorded from Panama and the western coast of Central 

 America by Hartlaub in 1895 and by myself in 1908 under the name of rfiomboidea. 

 These are here considered as tanneri. 



