208 WEST AMERICAN SHELLS 
glossy, but the outside is slightly rough. With the 
aid of a microscope one may see a fine system of 
minute lines and meshes. Its color is peculiar, be- 
ing a rich, rosy pink, very beautiful. These little 
shellsare found on the stems of sea-fans, which are 
brought up from tolerably deep water. To these 
they cling like a parasitic insect; hence their name, 
which really means ‘‘louse-shell.’? When fully 
grown the shell may be nearly half an inch long, 
though most specimens are much smaller. 
Another fine shell found on our 
coast is the one shown in Figure 
222, named Cyprea spadicea, Gray, 
the Nut-brown Cowry, (Luponia 
spadicea). It is our chief represen- 
tative of the great genus which is so 
abundantly developed in the warmer 
oceans. Cowries have smooth, 
well-rounded shells and are great 
favorites with the children, who de- Fig. 222 
light to use them for playthings. When young, the 
shells are thin and conical, with a short spire and 
a large aperture. As time goes on the outer lip 
inereases in size and thickness, while the spire be- 
comes completely hidden under the advancing 
whorls. In color, the lips of this shell are white, 
while on the back there is a ring of dark brown, 
with a central part of a hghter shade of the same 
eolor. I have in my collection an aged specimen 
that is over two inches in length, but such a size 
is the exception. This species is found in the 
south, but never in great numbers. When taken 
