Subfamily Aristeinae Alcock. 

 Benthesicymus Sp. Bate. 



The genus Bcnthesicxmus includes at present 13 species, 3 or 4 of which are confined 

 to the Atlantic. Boith. iridcscens Sp. Bate and Bcnth. mollis Sp. Bate are only Icnown froni 

 the island of Tristan da Cunha, Benth. longipes Bouv. has been recorded from the Cape Verde 

 Islands, the fourth hnally, Bentli. iiioratiis S. I. Smith, does not only occur on the east coast 

 of the United States and near the Tortugas, but also on the coast of Morocco and off the 

 Cape Yerde Islands, while it has even been recorded by Miss R.\thbun from the Hawaiian 

 Islands. Four other species are not only found in the Atlantic, but also in the Indopacific. 

 These species are i" Bcnth. Bartletti S. I. Smith, which is distributed from Xova Scotia to 

 the Gulf of Mexico and the Cape Verde Islands, but which, according to Col. Alcock, occurs 

 also in the Bay of Bengal, 2° Bcnth. altiis Sp. Bate, known from the Kermadec, the Philippine 

 and the Fiji Islands and from Japan, but which Spence B.\te also records from Tristan da 

 Cunha, 3" Benth. pleocanthiis Sp. Bate, a species observed not only in the North Pacific and 

 off the Philippines, but also off Sombrero Island, one of the Antilles and, finally, 4" Benth. 

 brasiliensis Sp. Bate, known not only from the east coast of Brazil, but also from the South 

 Pacific, Torres Strait, New Zealand, the Fiji Islands etc. Benth. Tanneri Fa.x. is distributed 

 from California to Ecuador and the Galapagos Islands, while the four remaining species are 

 confined to the Indopacific. Of the latter Benth. laciniattis Rathb. has been taken near the 

 Hawaiian Islands and Benth. crcnatus Sp. Bate in the Low Archipelago; Benth. Investigatoris 

 A. And. was captured by the "Investigator" ïn the Andaman Sea and in the Gulf of Manar, 

 while it has been dredged off Saya de Malha, but this species occurs also near the Hawaiian 

 Islands, the fourth, Benth. arniat^is MacGilchrist, inhabits the Arabian Sea. 



Only one species, viz. Benth. Investigatoris., has been taken by the "Siboga", but two 

 other ones, viz. Bcnth. altiis Sp. Bate and Benth. brasiliensis Sp. Bate, will probably once 

 prove to be also inhabitants of the East Indian Archipelago. 



All the species of Benthesicymus are truly abyssal, inhabiting the great depths of the 

 Oceans. The greatest depth at which this genus has been observed, is that of 3050 fathoms 

 in the North Pacific {Benth. pleocantJms), but the .same species was taken near the Philippine 

 Islands at 1050 fathoms and off Sombrero Island in water of 450 fathoms. This great 

 variability as regards the vertical distribution has also been observed in some other species of 

 this genus. 



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