240 LITTORINA. 



Genus LITTORINA, Fer., 1821. 



Section Littorina (sensu stricto.) 

 L. GRANDis, Middendortf. Plate 41, fig. 80. 

 Solid, whorls a little concave round the upper part, smooth or ob- 

 soletely keeled, spirally striated towards the apex ; bluish grey, the 

 keels more or less interruptedly banded with chocolate, edge of lip 

 with a few chocolate spots. Length, 40 mill. 



Sea of Ochotsk. 

 L. 8QUALIDA, Brod. & Sowb. PI. 41, fig. 81. 



Solid, slightly striate, greenish grey, with narrow chestnut bands, 

 outer lip with chestnut markings, columella white, last whorl ven- 

 tricose, a little concave above. Length, 1 in. 



Netv Zealand. 

 L. LiTTOREA, Linn. PI. 41, figs. 82-85. 



Solid, smooth, spirally striated, sometimes impressed round the 

 upper part of the whorls; dark brown, olivaceous, yellowish or red- 

 dish, usually spirally lineated with a darker shade, interior of aper- 

 ture chocolate brown. Length, 25-40 mill. 



Euroj)e ; Northern Coast of United States (introd.). 



This is the common edible periwinkle of Europe, which of late 

 years has been observed as an inhabitant of the rocky coasts of the 

 New England States, spreading southward with wonderful rapidity. 

 The name periwinkle is supposed to be a corruption of 2)etty winkle 

 or whelk, in contradistinction to the whelk or winkle proper, Avhich 

 is Buccinum undafum. The extent to which this mollusk is con- 

 sumed is indicated by the late Dr. Jeffreys, who states that in the 

 Billingsgate Market of London, about 65,000 bushels are sold an- 

 nually. They are also utilized in keeping oyster beds free of sea- 

 weed. Fig. 82 represents an abnormally-shouldered specimen. 



The synonyms include L. vulgaris, Sowb., and L. ustulatus, Lam. 



L. SiTCHANA, Phil. PI. 41, figs. 86-91 ; PI. 45, fig. 12. 



Subglobose, moderately solid, strongly spirally ridged, usually 

 with subequal intervening furrows; dark chocolate color, often 

 with a broad white peripheral band, interior chocolate. 



Length, 15-18 mill. 



Vancouver's IsL, twrthward ; Japan and north coast of A»la. 



This is very close to L. rudis, Donov., with which it has been 

 identified by some of the Californian conchologists, and very possi- 

 bly it is a variety of that species; but it appears to vary constantly 



