Norwich Castle Museum, 129 
the Channel Islands ; we have already had occasion to 
refer to this genus when speaking of the beautiful 
exotic examples to be found in the collection of 
Foreign shells (p. 113), with which this, although a 
very pretty shell, will not compare. The animal lives 
on rocks and stones at the marvin of low water. 
Scissurella, a minute genus of Northern habitat is 
not represented in the collection, and we pass to the 
family of Trocuip, which is a very extensive one 
universally distributed, and extending from low water 
to a depth of upwards of too fathoms. The shells are 
for the most part nearly flat on the base, pyramidal in 
shape, pearly inside, with a horny operculum, and 
many of them, as will be seen, very prettily coloured. 
The first genus, Cyclostrema, which was established by 
Capt. Marryat, a Norfolk man, is represented in our 
‘collection by C. zzzfens and C. serpuloides ; its three 
members are extremely minute, and none of them are 
known to occur on the Norfolk coast; of the genus 
Trochus there is a good representative collection. 
Phasianella pulla, the Pheasant Shell, the only 
member of the family Tursinrp#, found in our seas, 
belongs to an essentially southern genus, and is repre- 
sented by some very pretty specimens from the 
Channel Islands. Of the family Lirrorinip we have 
a fair collection, including of course our common 
“periwinkle,” very abundant on some parts of the 
coast, and the collecting of which for sale forms a 
considerable industry; these are succeeded by some 
very minute shells belonging to the genus /azssoa. 
Passing over a number of other species equally small, 
we come to the genus Zurritella, or “‘Screws,” the 
shell of which is a slender elongated pyramid ; this is 
followed by Zruncatella, having the appearance of 
a truncated form of the preceding species; and 
some very pretty little shells of the genera Scalaria 
I 
