1869.] 125 [Perkins. 



LITTORINHm 



Littorina Ferussac, 1821. 



Littorina palliata De Kay, Moll. N. Y., p. 106, pi. vi, fig. 10. 

 Turbo palliatus Say, Am.. Conch., p. 82, 1822. Littorina littoralis 

 (Forbes & Plan.) Stimps., Shells of N. E., p. 33. 



Littoral, common on stones near low water, and on alga. Animal 

 varying in color from white to black; tentacles usually dark, rarely 

 light, tapering, broad ; eyes on their outer bases; foot oval or round; 

 operculum thin, oval, with concentric lines of growth. The animal 

 is very active, the tentacles are constantly m motion, and the pulsa- 

 tions in the head plainly visible. 



MEASUREMENTS. 



Length of shell 6 mill. Breadth 8 mill, 



foot 7.6 " " 3 " 



" tentacles 4 " 



" operculum 4 " " .6 " 



Littorina rudis Gould, Invert. Mass., p. 257, fig. 165 ; De Kay, 

 Moll. N. Y., p. 104, pi. v, fig. 103. Turbo rudis Montagu, Test. Brit. 

 Turbo obligatus Say, Am. Conch., p. 82, 1822. 



Common with the preceding. Animal dark; tentacles slender, 

 pointed, black above, lighter below; eyes on the outer bases ; ros- 

 trum black, two thirds as long as the tentacles ; foot whitish beneath, 

 dusky above, longitudinally grooved; operculum horny, oval, with 

 spiral lines of growth ; lingual ribbon very long and narrow ; ova 

 hatched within the animal; young shells flat, with very wide aper- 

 ture, corneous. 



MEASUREMENTS. 



Length of shell 10 mill. Breadth 8 mill. 



" foot 7.6 " " 3.6 " 



" opei-culum 4 " '• 3.2 " 



" tentacles 3.2 " 



Littorina irrorata De Kay, Moll. N. Y., p. 106, pi. vi, fig. 105. 

 Turbo irroratus Say, Am. Conch., p. 81, 1822. Phasianella sulcata 

 Lam. (teste Stimpson). 



Not at all common. 



LACUNID^. 



Lacuna Turton, 1827. 

 Lacuna vincta Gould, Invert. Mass., p. 262, fig. 178; De Kay, 



