682 BULLETIN 82, UNITED STATES NATIONAL MUSEUM VOLUME 1 



Helga station S.K. 223; off southwestern Ireland (lat. 5307' N.,long. 1450' W.); 

 749-914 meters [A. H. Clark, 1913] (2, Dublin M.). 



Helga station CXX; off southwestern Ireland (lat. 5358' N., long. 1224' W.); 

 698 meters; May 24, 1901 [A. II. Clark, 1913] (1, U.S.N.M., 35778). 



Helga station S.R. 151; off southwestern Ireland (lat. 5417' N., long. 1133' W.); 

 709 meters; August 27, 1904 [A. H. Clark, 1913] (3, U.S.N.M., 35774, 35775, 35901). 

 Type locality. 



Ingolj station 44; southwest of the Faroe Islands (lat. 6142' N., long. 936' W.); 

 997 meters; temperature 4.8 C. [A. H. Clark, 1923] (1, C.M.). 



Geographical range. From the northern part of the Bay of Biscay to southwestern 

 Ireland, and northward to southwest of the Faroes. 



Bathymetrical range. From 698 to 997 meters; the average of 5 records is 803 

 meters. 



Thermal range. The single record is 4.8 C. 



History. This species was first described in 1912 from 5 specimens which had 

 been dredged by the Irish Fisheries steamer Helga in 1904 and 1905, and at the same 

 time a sixth was recorded, under the name of Trichometra delicata, which had been 

 taken by the same ship in 1901. 



But the species had first been taken some years before, for in the Ingolj collection 

 I found one from station 44 which I recorded in 1923. 



Some years ago Dr. E. J. Allen, then Director of the Marine Biological Associa- 

 tion station at Plymouth, England, was so kind as to send me for examination some 

 of the specimens of Neocomatella europaea which had been dredged off the coast of Brit- 

 tany by the Huxley in 1906, and among them I found another example of this little 

 species. 



Genus TONROMETRA A. H. Clark 



Anledon (part) P. H. CARPENTER, Quart. Journ. Micr. Sci., new ser., vol. 27, 1887, p. 386, and fol- 

 lowing authors. 



Thaumatometra (part) A. H. CLARK, Proc. Biol. Soc. Washington, vol. 21, 1908, p. 128. 



Trichometra (part) A. H. CLARK, Notes Leyden Mus., vol. 34, 1912, p. 147. 



Tonrometra A. H. CLARK, Journ. Washington Acad. Sci., vol. 7, 1917, No. 5, p. 128 (referred to the 

 Bathymetrinae), p. 130 (diagnosis; type species Antedon remota P. H. Carpenter, 1888; range; 

 included species); No. 16, p. 510 (in key; range); Unstalked crinoids of the iSzftoja-Exped., 1918, 

 p. 244 (in key; range), p. 258 (key to the included species); Journ. Linn. Soc. (Zool.), vol. 36, 

 1929, p. 662. GISLEN, Rep. Swedish Deep Sea Exped., vol. 2, Zool., No. 4, 1951, pp. 55, 56. 



Diagnosis. A genus of Bathymetrinae in which the centrodorsal is hemispherical 

 or rounded conical with the cirrus sockets alternating or in irregular vertical columns; 

 there are 18 to 37 cirrus segments, of which the longest are strongly constricted centrally 

 with very prominent ends and may be over twice as long as their median widths; the 

 distal segments may be shorter or longer than wide; the IBr series and arm bases are 

 in close lateral contact; the brachials are more or less spinous at their distal edges; 

 P! is very long and delicate with 13 to about 21 segments, of which not more than two 

 or three at the base are as broad as long; P 2 is usually similar but may be slightly 

 shorter; there are no marsupia on the genital pinnules. 



Type species. Antedon remota P. H. Carpenter, 1888. 



Geographical range. In the Southern Ocean between Marion Island and the 

 Crozets, the South Orkney Islands and from off Princess Elizabeth Land, also from 

 east of Halmahera and the Lesser Sunda Islands in the East Indies. 



