18 I>-TRODUCTION TO COXCHOLOGY. 



But the most striking instance of gradual development 

 is shown in the Tiger Cowry^ C. tigris. The colour is at 

 first of an uniform chesnut bay^ but afterwards seems to 

 break into bands of close-set waved blotches of a richer hue, 

 a coating of which is then super-imposed, and upon that is 

 deposited a series of rather distant zigzag flames upon a 

 white ground. Thhdly, the mollusk turns his attention 

 towards the formation of teeth, and a few coloured spots 

 become apparent round the outer side. In the next stage, 

 a second layer of white enamel is added, but considerably 

 thinner and more dehcate than the preceding, through 

 which zigzag flames may be seen of a milky hue, and upon 

 this surface a number of dark spots are deposited. These, 

 again, are overspread by a thin white coating, intermixed 

 with numerous rich black and brown spots, showing for the 

 first time a narrower dorsal line, mostly edged with reddish 

 brown, ha^ing also the first deposit of dark spots over- 

 spread with a bluish transparent milky hue. 



Many of these splendid mollusks inhabit the shores of 

 the Pearl Islands. They are uniformly found in shallow 

 water under rolled masses of Madrepore, for they never 

 expose themselves to the sun^s rays. On lifting one of these 

 masses, a Tiger Cowry was generally observed, with his 



