276 



REPORT 1867. 



given by Forbes, as if from greater age), Chione islandica, Venus sarniensis, 

 y. fasciata, Solen peUucklus, Saxicava arct'ica, Lima Mans, or L. Josiconii (a 

 single valve from thirty-five fathoms) ; Pectens, numerous, among them F. 

 tlgrinus, but all empty shells ; Dentaliiim entails ; D. tarentinum (?), Pilidium 

 fulvum, on the dead shell oi Pinna nigra; Fasus 2^1'opinquus ; F.longirostns, 

 from fortj^ fathoms ; Bulla lignana ; Turritella terehra ; Troclms papillosus ; 

 Scalaria clathratulus ; Natica alderi; N. niticla, from the stomach of Asterias 

 aurantiaca ; Pandora imequivalvis ; two or three examples of a genus which 

 Forbes terms Trophon, but of which he has not given figures ; Emarginula 

 rosea ; Marginella rosea. 



Ceustacea. — The Reporter states that the number of Crustacea that have 

 been taken off this south-western coast of England has been very large, 

 being, with few ai'ctic excejjtions, the whole that have hitherto been known to 

 the British seas, to which we have the pleasure of adding several interest- 

 ing and important species. 



The entrance to the English channel appears in its position to be the 

 boundary or extreme limits of two several faunas. We find species that are 

 decidedly arctic in their character rejjresented by specimens that have a 

 generally depauperized appearance, both as to size and tyjncal expression, 

 while Mediterranean species are represented without any large amount of 

 variation in form or dimensions of specimens. But our observations induce 

 us to believe that the southern forms, when taken on our shores, are gene- 

 rally dredged from water of considerable depth, whereas those of the arctic 

 types are as invariably taken in shallow water. 



The variation of depths and local habitats appear to us to depend more 

 upon the condition of food and its general supply than from other causes ; 

 we therefore think that the geographical distribution of animals in limited 

 regions can only be worked out by a previous knowledge of the history of the 

 animals, particularly in relation to their food — and even then cannot be very 

 rehable. 



The annexed list of Crustacea exhibits the various species that have been 

 recently taken by members of this Committee. 



Beachyura. 



