LTTTORINID^. 241 



The foot is divided by a longitudinal line and in walking the 

 sides advance alternately. The periwinkle and trochus are the 

 food of the thrush, in the Hebrides, during winter. The lingual 

 canal of the periwinkle passes from the back of the mouth under 

 the CBSophagus for a short distance, then turns up on the right side, 

 and terminates in a coil (like spare rope) resting on the plaited 

 portion of the gullet. It is 2^ inches long, and contains about 

 600 rows of teeth ; the part in use, arming the tongue, comprises 

 about 24 rows. 



The species above referred to, L. littorea, is an exceedingly 

 numerous mollusk of Northern Europe; it appears to have 

 become naturalized on the New England coast, where its area 

 is rapidly increasing. It is largely consumed as an article of food 

 in Europe, not only at the sea-ports and fishing villages, but 

 even at the great capitals; 1900 tons of it being sold annually 

 in London and employing a thousand persons in gathering it. 

 It is also extensively used as bait, and to keep the oyster grounds 

 clear of sea-weed — for which purpose the Essex oystermen regu- 

 larly distribute many bushels of winkles over their grounds. 



Many of the large species, including the above and the 

 American species L. irrorata^ Say, are in a great measure amphib- 

 ious, living on the rocks along the shore, where they are washed 

 by the tide. Several individuals of a West Indian species, sur- 

 vived deprivation of water for more than a year in my cabinet. 



MELARAPHis, Muhlfcldt. Shell rather thin, conical, with pointed 

 spire ; surface with revolving stride, and usually variegated with 

 brilliant colors. Tropical and subtropical. L. angulifera, Linn. 

 (Ixix, 20). 



NERiTOiDES, Browu. (Neritrema, Recluz.) Shell short turbi- 

 nated or subglobose ; spire very short, with obtuse apex ; solid, 

 inner lip much thickened and excavated. L. obtusata, Linn. 

 (Ixix, 21). 



CYCLONEMA, Hall. Shell somewhat thinner than in the living 

 Littorinffi. Palaeozoic. 40 sp. U. S., Europe. L. cancellata, 

 Hall (Ixix, 22). 



RAULiNiA, Mayer, 1864. Shell turbinate, ovate-oblong, rather 

 thin, spirally sulcate ; aperture ovate-oblong, margin simple, 

 angulate behind, subeffuse in front ; columellar lip wide, arcuate, 

 with a central tooth. Fossil. Paris basin. A living Australian 

 species. L. aUigata, Desh. (Ixix, 23). 



A large number of palaeozoic, mostly smooth shells like Platy- 

 ostoma, Conr., Holopea, Hall, Macrocheilus, Phillips, etc., which 

 are generally referred elsewhere, maj'^ very probably belong to 

 Littorinidse. 



