THE COLOURS OF COWRIES 357 



of which there is both a long and a short form, the bands 

 tend to become very indistinct ; and it may be suggested 

 that the short form is not far removed from the ancestral 

 type of the beautiful orange cowry, which is one of the few 

 uniformly coloured species ; such uniformly coloured forms 

 indicating, as already said, one line of specialisation. 



Among the spotted cowries several types are noticeable. 

 Firstly, we have species in which the back of the shell is 

 simply spotted with black or brown, among them being the 

 tiger cowry (C. tigris), the panther cowry {C. pantherina), 

 and the much smaller lynx cowry {C. lynx). As all these 

 have a comparatively short and wide shell, they indicate 

 an advanced type. Next we have white-spotted cowries, 

 such as the false Argus {C. cervus), the lesser false Argus, 

 and the fallow-deer cowry ; and as the two former are 

 long-shaped, while the latter is comparatively short, they 

 seem to indicate a medium stage of evolution. 



From the black- and brown-spotted forms seem to have 

 originated the group represented by the map and nutmeg 

 cowries {C. mappa and arabicd), in which the spots are 

 retained along the margins of the back of the shell, the 

 central area of which is more or less finely reticulated or 

 vermiculated, the map cowry taking its name from the width 

 and sinuosity of the line between the mantle-lobes. In the 

 typical nutmeg cowry the reticulations are very nutmeg-like, 

 but in other specimens more or less distinct pale spots are 

 dotted all over the central area, till in the variety histrio 

 the spots are the dominant feature, being only separated by 

 these lines so as to form a kind of network, or honeycomb 

 arrangement. Perhaps the cullender cowry may be regarded 

 as an offshoot of this type. 



But another modification may apparently also be traced to 

 the arabica-mappa stock, the members of which are inter- 



