126 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



Purpura lapillus (Linn6) Lam. Gould, Inv. Mass., II, p. 360, 1870. Ver , Inv. "V. S., 

 p. G42, 1874. 



Shore, rare. 



Anachis avara (Say) Perkins. Ver., Inv. V. S., p. 643, 1874. Gould, Inv. Mass., I, p. 

 313, 1841 ; li, p. 356, 1870 ( Columbella). 



Eare ; only a single specimen was found by the writer, but others have 

 collected it at Provincetown. 



Astyris lunata (Say) Dall. Ver., Inv. V. S., p. 645, 1874. — Columbella liinata Gould, 

 Inv. Mass., il, p. 359, 1870. 



Abundant in the eel-grass in front of the town and off the dike. 



Lunatia heros (Say) Adams. Gould, Inv. Mass., II, p. 338, 1870. Ver., Inv. V. S., p. 

 646, 1874. 



Yery common along the entire inner shore, and often picked up dead 

 on the outer beaches. 



Neverita duplicata (Say) Stimp, Gould, Inv. Mass., II, p. 345, 1870. Ver., Inv. V. S., 



p. 646, 1874. 



Abundant, associated with Lunatia heros. 



Littorinella minuta (Totten) Stimp. Ver., Inv. V. S., p. 653, 1874. Gould, Inv. Mass., 

 II, p. 298, 1870 (Rissoa). 



Common, shore at low water. 



Skenea planorbis (Fabr.) Forbes and Hanley. Gould, Inv. Mass., II, p. 296, 1870. 

 Ver. , luv. V. S. , p. 655, 1874. 



Common on the shore, with Tottenia gemma, Littorinella minuta, &c., 

 and also on the piles of wharves. 



Littorina littorea (Linn6) Johnston. Gould, Inv. Mass., II, p. 308, 1870. 



Very abundant on the shore, on piles of wharves, and on eel-grass 

 which is more or less exposed at low tide. Just off the dike it occurs 

 on the eel-grass in countless numbers, and, in common with all the other 

 species of shells in that ^^cinity, is frequently covered with the white 

 calcareous tubes of Hydroides dianthus. 



Littorina rudis (Maton) Gould, Inv. Mass., I, p. 257, 1841 ; II, p. 304, 1870. Ver., Inv. 

 V. S., p. 651, 1874.— X. tenebrosa Gould, In 7. Mass., I, p. 2.59; II, p. 306. 



This is an exceedingly common species on the shore. 



Littorina palliata (Say) Gould, Inv. Mass., I, p. 260, 1841 ; II, p. 309, 1870. Ver., Inv. 

 V.S.,p.652, 1874. 



Common on the shore and on piles of wharves among sea-weeds. 



Lacuna vincta (Mont.) Turton. Gould, Inv. Mass., II, p. 302, 1870. Ver., Inv. V. S., 

 p. 652, 1874. 



On the eel-grass, shallow water; not found in much abundance. 



