352 MOSTLY MAMMALS 



the islanders of Eastern Asia for personal adornment, for 

 weighting their fishing nets, and as a means of exchange ; 

 while in the latter respect the well-known money cowry has 

 a still more extensive use over a large part of Asia. 



But it is from the peculiarities of their structure and 

 coloration that these beautiful shells claim our attention in 

 the present article. Taking any common species, it will be 

 seen that the upper surface of the shell approaches more 

 or less to an egg-shape, with a notch at each extremity 

 forming the terminations of the mouth below. Somewhat 

 to the right of the middle line in most species runs a 

 straight or slightly sinuous line over which the pattern of 

 the rest of the upper surface does not extend, this line 

 marking in the living animal the limits of the right and 

 left lobes of the so-called mantle, which during activity 

 extends upwards from the foot on which the creature 

 crawls to develop the rest of the shell. Compared with 

 an olive, in which the spire is relatively small, the shell of 

 an adult cowry differs by the rudimentary condition or 

 even absence of a spire ; while on the under-surface the 

 narrow mouth of the shell (not, be it understood, of the 

 animal) is remarkable for the series of vertical ridges, or 

 " teeth," with which its edges are armed. 



Now, since almost all other univalve shells related, even 

 remotely, to the cowries, have a more or less elongated 

 spire at the hinder or upper end, the inquirer naturally 

 seeks to find out the reason for the disappearance of this 

 part in the members of the present group. In a fully 

 adult specimen of the common black-spotted tiger cowry 

 no trace at all of the spire can be detected, but in the 

 equally common Surinam-toad cowry a more or less distinct 

 remnant, partly buried in the abundant cement, is observable 

 even in the adult. In Scott's cowry the spire is much 



