124 THE FAUNA OF THE DEEP SEA 



Mr. Brady, in writing the report of the ' Challenger ' 

 Ostracocla, came to the conclusion that they do exist 

 in very limited numbers in the*most profound depths 

 of the sea ; but it is nevertheless quite possible that 

 all the Ostracods brought on deck by the trawl or 

 dredge were really captured either on the way down 

 or on the way up, and are, strictly speaking, pelagic 

 in habit. 



Similar caution must be taken in dealing with the 

 Copepoda, an order of Crustacea that is essentially 

 pelagic in habit. The only species that has been 

 regarded as undoubtedly abysmal is Pontostratiotes 

 cibyssicola, a form whose carapace and antennas are 

 armed with exceedingly long and strongly toothed 

 spines, and was found in the mud brought up by the 

 trawl from a depth of 2,200 fathoms. 



Calamus princeps, the largest species of its genus 

 of a deep reddish brown colour, may also belong to 

 the fauna of the deep sea, but we have less evidence 



* 



concerning the habitat of Hemicalamw acideatus, 

 Phyllopus bidentatus, and some of the Euchgetas. 



The Amphipoda seem to be but poorly re- 

 presented in the fauna of the abyss ; in fact it may be 

 considered to be still an open question whether any 

 Amphipods habitually live in very deep water. 



