16 



BULLETIN 75, UNITED STATES NATIONAL MUSEUM. 



It is worthy of note that eight of these eleven species belong to the 

 Oceanic fauna, two to the Bering, and only one to the Honshu area, 

 which certainly supports the view that species with a great bathymet- 

 rical range tend to become widely distributed. 



Three other species (Ophiura flagellata, OpJiiacanfha pentagomi, 

 Asfironi/.c loveni) have a bathymetrical range of over 800 fathoms. 

 Two of i hese belong to the Oceanic fauna and the third is very widely 

 distributed in the Kast Indian region. There are fourteen addi- 

 tional species which have a bathymetrical range of over 500 fathoms, 

 and live of these belong to the Oceanic fauna. We see therefore that 

 of i lie eighteen species belonging to that fauna fourteen have a 

 bathymetrical range of over 500 fathoms, which lends support to the 

 proposition that species occurring on both sides of the North Pacific 

 have a great bathymetrical range. 



Of the 15S species of whose temperature range we have some 

 record, one (Ophiura bwichyactis, two stations) was taken only in water 

 colder than '.-}'2' J and the following seven were taken only below 36: 



Ophiura '<///>/(/./-. two stations. 

 Ophiiirn liii/lii/hin, four stations. 

 Anthophiura m-in/ut/u, one station. 



Am jiliili pin /i/n/t/ttilii, | wo stations. 



Ophiacantha eurypoma, one station. 

 Ophiacantha omoplata, one station. 

 Ophiolebes brachygnatha, two stations. 



While there can be no doubt that all of these eight species are 

 characteristic of very cold water, the importance of the list is vitiated 

 by the fact that three of the species were taken at only a single sta- 

 tion each, and only one is recorded from more than two stations. 



There are forty-two other species which were not taken in water 

 warmer than 40 and twenty-three more which were not found above 

 45. It is therefore fair to say that not less than 38 per cent of the 

 189 species in the collection are distinctly cold-water species, and this 

 is rather remarkable when we consider that less than 30 per cent of 

 the 189 belong to the Bering and Oceanic faunas combined ; that only 

 16 per cent are really deep-water species, and that nearly 80 per cent 

 were taken in less than 100 fathoms. 



On the other hand, there are forty-one species which were not 

 taken in water colder than 50, and there is every reason to believe 

 that at least two-thirds of those species for which no temperature is 

 recorded (such as the two species of Optdocoma, the two species of 

 Ophioplocus, four species of Ophiothrix, etc.) belong in the same class. 

 Moreover, there are nineteen additional species which were taken in 

 water warmer than 60, and two of these occurred at a temperature 

 higher than 70. It is not unreasonable, therefore, to say that the 

 number of distinctly warm-water species nearly or quite equals that 

 of the cold-water forms. 



