THE COWRIES AND SHELL MONEY. 



Among marine mollusks none .stand so 

 favorably in the eyes of collectors or are 

 so beautiful as the Cypraeas, or Cowry 

 shells. With their glossy coats and varied 

 colors they are indeed gems of the ocean, 

 and it is little wonder that the concholo- 

 gist has placed them first among the 

 many families of marine shells. 



The name Cpyraea comes from Cypris, 

 one of the names of the goddess Venus. 

 About two hundred recent species have ^ 

 been described and they are found in 

 nearly all parts of the world, though 

 more numerous in the tropics and sub- 

 tropics, where they live on coral reefs 

 and under rocks. As in many other 

 genera of shells the Cowries living in the 

 tropics are more brilliantly colored than 

 those from more temperate climes, a 

 condition due to the large amount of sun- 

 shine and high temperature, both of these 

 factors being essential to the secretion of 

 color in the pigment cells of the animal. 



The animal which inhabits a Cowry 

 shell is a curiosity. The foot is large 

 and spreads out in a wide mass, enabling 

 the animal to glide along quite rapidly. 

 The mantle lobes are folded over the 

 back of the shell and are beset with many 

 little tuft-like organs which stick out 

 like young shoots on a plant. The 

 mouth is placed at the end of a rather 

 long snout or rostrum and the eyes are 

 upon the outside of two long, tapering 

 tentacles, about one-third the distance 

 from the body. When the shell is young 

 it is covered with a thin epidermis and 

 has a thin, sharp outer lip, like some 

 snails, but when it is full grown the 

 outer lip rolls inward, becomes toothed or 

 ridged, as does also the inner lip, and 

 the aperture becomes a long and nar- 

 row slit reaching from the apex to the 

 base of the shell. The mantle lobes, 

 which are inconspicuous in the young 

 shell, becomes larger and are reflected 

 over the back, depositing coat after coat 



of shelly enamel until the first pattern of 

 the shell, as well as the epidermis, is cov- 

 ered with a secondary, shining coat. On 

 most Cypraeas there is a line of paler 

 color, showing where the two lobes of 

 the mantle meet on the back. 



Like many other mollusks the Cypraea 

 is able to dissolve the internal whorls and 

 thus enlarge the capacity of its shell. 

 This is also true of Conus, and Murex, 

 and some other marine snails dissolve 

 the spines which may be in the way when 

 increasing the size of the whorls. The 

 older naturalists, Lamarck and Bru- 

 guiere, believed that the Cypraea was able 

 to dissolve its outer lip after it had been 

 rolled over and toothed, but this theory 

 has been proved to be incorrect. They 

 founded their belief on the fact that some 

 individuals of the same species were 

 larger than others. This, however, is due 

 simply to individual variation. 



The beautiful colors so much admired 

 are deposited by the reflected mantle and 

 their variety is almost endless. Some 

 pre perfectly plain, white, brownish, yel- 

 lowish or orange, others are spotted with 

 red, white, brown, drab or black, and 

 still others are variously banded. The 

 eyed-cowry (Cypraea argus) has large, 

 dark brown spots on a lighter back- 

 ground. 



In form and sculpture the Cowries pre- 

 sent a rather wide range of variation. 

 The typical form is more or less cylin- 

 drical, or pyriform, while others are flat, 

 oval or egg-shaped. The surface varies 

 from smooth to spirally lined and pus- 

 tulose. In size they vary from the little 

 Trivia exigua, scarcely one-fourth of an 

 inch long, to the huge Cypraea testudi- 

 naria, nearly five inches in length. 



Many of the larger species, like the 

 tiger cowry (Cypraea tigris) and the 

 black cowry (Cypraea mauritiana) have 

 been household ornaments for centuries 

 and have also served as playthings for 



