392 BULLETIN 82, UNITED STATES NATIONAL MUSEUM VOLUME 1 



hydroids, the smaller pycnogonids, Chiridota laevis, Molpadia borealis and Diastylis 

 goodsiri, and in lesser numbers Pteraster militaris, Sabinea septemcarinata, Idothea 

 sabinei, Munnopsis typica, Anonyx lagena, Acanthozone cuspidata, Podocerus anguipes, 

 Aegina echinata, Alcyonidium, sp., Lucernaria, sp., and several species of mollusks and 

 starfishes, together with the immense pycnogonid Collosendeis gigantea. He writes that 

 such characteristic animal species as Collosendeis gigantea, the pennatulid mentioned, 

 Cleippides quadricuspis and Solaster tumidus give a remarkable interest to this associa- 

 tion. 



This Antedon-Astrophyton, or more properly Heliometra-Gorgonocephalus, associa- 

 tion has been subsequently noted, more or less developed, in various other places, 

 mostly in the vicinity of Spitzbergen. It seems to mark the areas where abundant 

 plankton is continually delivered over a bottom not firm enough for development 

 of the large arborescent coelenterates, such as Primnoa, and to be composed of plankton- 

 feeding types together with animals which abstract the food collected by them or feed 

 directly upon them, and others which consume the organic detritus lying on or mixed 

 with the cold surface mud. 



While in the Arctic and north Atlantic oceans the ranges of Heliometra glacialis 

 and of Gorgonocephalus eucnemis are practically the same and the latter lives between 

 38 and 1187 meters, in the Pacific the conditions are quite different. Here Heliometra 

 is confined to the Sea of Okhotsk and to the western side of the Sea of Japan, where 

 it lives under strictly arctic surroundings, but Gorgonocephalus eucnemis is very widely 

 distributed, occurring both further southward in the Eastern Sea and much further 

 northward to and throughout the Bering Sea, where it is especially abundant, and 

 thence southward along the American coast to California, here and in the Bering Sea 

 being associated with the species of Florometra. Furthermore Gorgonocephalus eucnemis 

 is found in temperatures as high as 15.89 C. 



In the Okhotsk and Japan Seas Gorgonocephalus eucnemis was found by the Alba- 

 tross associated with Heliometra only at stations 4983, 49S6 and 5021. 



Occurrence of the pentacrinoids. The pentacrinoid young of this species have 

 been taken at the following localities : 



Davis Strait, 3 miles off Coutt's Inlet, 237 meters, and off Cape Raper, 110 me- 

 ters; Vfiringen station 48, east of Iceland, 547 meters, 0.3 C.; Michael Sars station 

 74, 1902, southeast of the Faroes, 1130 meters, +0.03 C.; Alexander Kovalevski sta- 

 tion 70, Kola Fjord, 91-128 meters; Vfringen station 312, west of Bear Island, 1203 

 meters, 1.2 C.; Vtfringen station 363, off the northwestern coast of Spitzbergen, 

 475 meters, +1.1 C.; Frithiqf, western Spitzbergen, 80-300 meters; Varna station 

 18, off the mouth of Kara Bay, 101 meters, 1.2 C.; Dijmphna, Kara Sea. 



All of the pentacrinoids dredged by the Porcupine in the "cold area" of the Faroe 

 Channel belong to Poliometra prolixa, none to this species. 



The pentacrinoids have been found from June 16 to September 13, which dates, 

 however, represent nothing more than the limits of the practicable working season in 

 the regions in which they occur. As they probably take nearly or quite, possibly over, 

 two years in attaining their full growth and as the breeding season in most of the deep- 

 er localities in which they occur is probably continuous throughout the year because 

 of the unva^ang conditions, intensive work in any rich region away from the shore 

 line should yield at any one time a good series of pentacrinoids in all stages. 



The depths at which they have been found vary between 80 and 1203 meters, 



