GASTEROPODA. 



161 



sea-weeds which grow among the stones in muddy and 

 shallow water; and that he found in the stomach of 

 several, small pebbles as in the gizzards of birds. He also 

 mentions that, when irritated, they emit a fine purplish- 

 red fluid, which stains the water for the space of a foot 

 round, and that, besides this means of defence, an acrid 

 secretion, which is spread over the body, causes a sharp 

 stinging sensation ; he found them at St. Jago. Forbes 

 says that they are perfectly harmless, though they have 

 been regarded with fear as poisonous and hurtful; but 

 there does not seem to be any foundation for this idea. 

 A. hybrida is found on the English coasts. The eggs are 

 said to be attached together in long lines like ribbons. 

 The animal is sometimes called the " Sea Hare." 



Philippi has the following as sub-genera: — Dolabella 

 Lam. ; Thallopus Sw. ; Aclesia Rang ; Aclesia Gray ; 

 and Bursatella Blain. 



Icarus. Forbes. — The animal differs from Aplysia, as 

 it possesses only two tentacula; the body is prolonged 

 into a long tail behind, and the shell is like that of a 

 Bullaea, even having a spiral apex. — 1 species. 



L Gravesii is found in the Egean Sea. 



Notarchus. Cucier. (Busiris Risso.) — The animal 

 differs from Aplysia in having the lobes of the mantle so 

 much united to each other that only a long cleft remains, 

 through which the water enters to the gills ; there is no 

 shell to cover the gills, and the sole of the foot is very 

 narrow. — Few species. 



Found in the Mediterranean. 



Lophocercus. Krohn. — The animal has the head 

 truncated, and bears on the angle two ear-shaped ten- 

 tacula ; lip appendages absent ; the mantle, cloven in the 



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