RISSOA. 151 



R. parva : smooth, variously coloured in flames. 



B. inconspicua : resembling E, parva. 



R, vitrcPM : long, smooth, transparently white, with the last 



whorl but one large. 

 B. prowima : very minute, striated. 

 R. ulvcs. : conical, smooth, pale yellowish-brown. 

 R. fulgida : microscopic, banded with brown, smooth. 

 R. littorea : smooth, globular. 



R. pidcliernma : very minute, coloured with square spots. 

 R. soluta: less globose than pulc/ierrima, striated. 

 R. anatina : smooth, short, with shouldered whorls. 

 R. veiitrosa : smooth, wliite, with rounded whorls. 



The habits of these minute animals are not so generally 

 known as those of some other more conspicuous genera ; for^ 

 although some of the kinds live in great numbers just under 

 the water's edge, it is only when dead that the shells are 

 thrown on the shore ; so that in proportion to their plen- 

 tiful distribution, comparatively few opportunities occur of 

 examining the animals, or of watching their movements. A 

 collector may have the tantaHzing pleasure of crushing under 

 his feet, in some places, myriads of these tiny shells on the 

 beach, day after day, for weeks, without once meeting with 

 a living specimen. Some of the species seem to have the 



