PART A MONOGRAPH OF THE EXISTING CRENOIDS 675 



Thermal range.— From 2.40° C. to 9.28° C; the average of 15 records is 5.39° C. 



History. — This species was originally described as Antedon cubensis by Count 

 Pourtal^ from two specimens dredged by the Bibb in 1869 off Cojima, Cuba, in 823 

 meters. The description given by Count Pourtal^s, though short, is quite sufficient 

 for its identification, cspeciallj^ when taken in connection with his comparison with 

 Hathrometra sarsi. He says at first that the centrodorsal is "conical", but later that 

 it is "flatter" than the centrodorsal of //. sarsi, which convej-s the impression that it 

 is rounded conical. Pi he gives as "not much longer than" Pj; probably tlic tip was 

 broken off, as in this species Pi is exceedingly delicate and somewhat stiffened. 



In 1878 Pourtal^ recorded under this name two additional specimens from Blake 

 station 43; but what he says about them does not at all accord with the original 

 description. 



The explanation of this discrepancy is that the smaller of the two original speci- 

 mens, which was very badly broken, was not of the same species as the larger and more 

 nearly intact from which the description was made, but was an example, the first to come 

 to light, of Atelecrinus balanoides, and the two from Blake station 43 represented the 

 same species. 



In his preliminary report on the comatulids collected by the Blake Dr. P. H. Car- 

 penter called attention to this confusion of two entirely distinct species. It was in this 

 paper (1881) that he first proposed the generic name Atelecrinus, using the specific 

 name cubensis for Pourtal^s' second specimen from the Bibb station and including the 

 two from Blake station 43 with others from various localities under the name balanoides. 



In 1908 I described under the name of Trichometra aspera an interesting little 

 comatulid which had been dredged by the Albatross in 188G between the Bahamas and 

 the North Carolina coast in 494 meters, and at the same time designated by the manu- 

 script name Trichometra americana another form from the fishing banks off New- 

 foundland which I beUeved to be distinct. The specimens of the latter I had found in 

 the U.S. National Museum collection bearing the name Antedon dentata. It was these 

 that I had in mind when discussing the relationships of Trichometra {Orthometra) 

 hibemica (1913). 



Dr. Clemens Hartlaub in 1912 published a detailed description and figures of a 

 specimen which he had found in the Blake collection with the name Antedon cubensis 

 in Carpenter's hand wTiting. He remarked that at least this had the "arm joints with 

 imbricated serrated edges," and I have no doubt whatever that it is really Pourtalfe' 

 original type specimen. Another specimen also labeled Antedon cubensis by Car- 

 penter was figured by Hartlaub; but this is quite different from the first and represents 

 Coccometra nigrolineata. 



Hartlaub's redescription and figure of Pourtales' type specimen enabled me at 

 once to recognize its specific identity with my Trichometra aspera, while a reexamina- 

 tion of all the material at hand showed that Trichometra americana (MS) also repre- 

 sented the same species. 



In the Siboga report (1918) I recorded Trichometra cubensis from 12 localities, 

 ranging from the Gulf of Mexico to the fishing banks off Newfoundland. 



Among the collections brought together by the Danish steamer Ingolf there were 

 several specimens of a species of Trichometra from S stations between Davis Strait 

 and the Faroe Islands. These specimens I had designated (again MS) as T. ingolfiana. 

 But a detailed study of all the available material made after the receipt of Hartlaub's 



