REPORT ON THE CEPHALOPODA. 233 



expanding to form clubs, and are armed with very minute suckers ; I have not observed 

 anything like a specialised tactile organ in either of these tentacles, or I should be disposed 

 to suggest an analogy between them and the long streaming fringes found in certain 

 deep-sea fish. The fact remains, however, that this form of tentacle is the only structural 

 character which I have observed to be common to any two deep-sea Cephalopods. The 

 stomach of one of Professor Verrill's specimens contained fragments of Crustacea, but we 

 have no other information regarding its habits and mode of life. 



It must be admitted that the evidence that this form came from the deep sea is by 

 no means conclusive, but it is very suggestive that no individuals should have been taken 

 in a surface net, while they seem to be not very uncommonly brought up by the deep-sea 

 trawl. 



Five species of Octopus (see p. 229), have been brought up from depths of over 500 

 fathoms, a particularly interesting fact since we are accustomed to consider these animals 

 as being characteristic of shallow waters. It seems unlikely, however, that they live at 

 the surface, for from what we know of the habits of this genus as observed in ac^uaria, 

 they seem rather to frequent the bottom, hiding in crevices of the rocks, and clinging to 

 them by their suckers, swimming only as a means of passing from one hiding place to 

 another ; the same remark applies also to the three species of Eledone [Eledone verru- 

 cosa, Eledone rotunda and Eledone hrevis), which also appear in the lists of deep-water 

 forms. 



Eledonella has only been twice obtained and on both occasions by a dredge that 

 had been clown to the abyssal regions (1100 and 2949 fathoms), but its semitransparent 

 consistency, resembling that of Cranchia and Taonius, is suggestive of its being a pelagic 

 organism. 



Alloposus mollis furnishes another problem for future investigation, both as regards 

 its habits and its systematic position. All the specimens obtained in a perfect state have 

 been brought up from considerable depths, and the tissues have a soft gelatinous character, 

 recalling Cirroteuthis ; perhaps this may be in some way correlated with deep-sea life ; 

 Giinther has pointed out that abyssal fish when brought up to the surface present a marked 

 flaccidity of their tissues. 



As regards the single specimen which forms the type of the new genus Promacho- 

 teuthis, I feel quite unable to give any opinion as to its habits. It was brought up by 

 the deep-sea trawl from a depth of 1875 fathoms, off the coast of Japan, but I have failed 

 to find any sufficient evidence to show whether it came from the surface or the bottom. 



The Taonoteuthids [Calliteiithis, Histioteuthis, &c.) form a group, whose bathymetrical 

 distribution presents a still unsolved problem ; perhaps the truth is that the species vary 

 in this respect. Verany records that his specimens of Histioteuthis were taken by the 

 dredge ; Calliteuthis has been taken by deep-sea dredges in depths varying from 345 to 

 2369 fathoms ; the only specimen known of Histiopsis was brought up by a trawl which 



(ZOOL. CHALL. EXP. — PART XLIV. 1886.) Xx 30 



