288 



Holbollii) Kroy. ; Callisoma crenata, Bate ; A inpelisca cari- 

 nata, Bruz. ; A . Belliana, Bate ; A mathilla Sabini^ Leach ; 

 Gammarus locusta, Linn. ; Caprella tuberculata, Guerin ; 

 Cirolana spinipes, M. Ed. ; Eurydice pulchra. Leach ; 

 A returns longicornis, Sow. ; A . gracilis, H. Goods. ; Idotea 

 tricuspidata, Desm. ; Diastylis Rathkii, Kroyer ,* Pandalus 

 annulicornis, Leach ; Hippolyte varians, Leach ; H. spinus, 

 Sow. ; Gebia deltura, Leach ; Galathea strigosa^ Linn. ; 

 G. dispersa, Bate ; Pagurus Icevis, Thomp. ; Ebralia 

 Cranchii) Leach ; Hyas coarctatus^ Leach ; Portunus 

 holsatus. Fab. ; P. pusillus. Leach. 



These are forms in which the destruction of shell fish 

 and Crustacea means the deprivation to the cod family of 

 a portion at least of their food ; and, unless that food had 

 previously been largely in excess, much destruction must 

 eventuate in either a decrease in the quantity of nourish- 

 ment for each individual fish, which would probably cause 

 them to become inferior in quality ; or else it would have 

 to be met by a decrease in the number of fish residing in a 

 given space of water. 



The last class I shall refer to are ground fish, Pleuro- 

 nectidce, as halibut, turbot, brill, soles, plaice, and other 

 marine kinds, the food of which varies widely from that 

 which is consumed by the gregarious surface swimmers, or 

 the more omnivorous midwater forms. Destitute of an air- 

 bladder, and generally with mouths comparatively smaller 

 than exists in the more predaceous members of the cod 

 family, we find them essentially ground feeders. Their 

 diet consists of almost any invertebrate form, by them shell- 

 fish and Crustacea are largely consumed, as are also small 

 fish and fish-eggs. Dr. M'Intosh, at St. Andrews, obtained 

 the following varieties of food from flounders captured 

 there : Pecten tigrinus, O. J. M tiller ; P. similis, Laskey ; 



