GAMMARUS. 
183 
Common on all the coasts of Britain. Colonel Montagu 
observes that this species is wholly marine, never quits the 
water by choice, is incapable of leaping, and seems to have 
very little use of its legs out of that element ; for when de- 
prived of water it lies on its side, and endeavours to force 
itself along by the action of its tail. If put into fresh 
water, it soon dies. 
Gammarus carinatus.'* — Body clouded with red and 
horn-colour, and sometimes with white, and sprinkled with 
minute yellow dots. Segments of the back strongly keeled, 
hind margins with distant granules. 
Berwick, often taken in baskets used for catching crabs. 
Gammarus marinus. Leach’s Coast Screw — The process 
between the antennae somewhat pointed. 
Hab. South coast of Devon. Strangford Lough (Thomp- 
son) ; Ballysodare, Sligo (Mrs. Hancock) . 
Gammarus Camptolops. Bent-eyed Coast Screw — Eyes 
flexuous, shaped somewhat like the letter S. Found in 
the sea near Loch Banza in the Isle of Arran (Dr. Leach) ; 
River Lagan, Belfast (Messrs. Hyndman and Thompson). 
Gammarus maculatus. Spotted Coast Screw . — Body 
smooth, glossy ; back dusky, with a faint yellow band 
* Dr. Johnston, Zool. Journ. iv. 52. 
