630 Natural History of Molluscous Animals : — 



called forth by the rudest treatment. As we observed this 

 interesting animal, with Milbert's florid description at hand, 

 I can aver that the red, aurora, and orange colours did not 

 present themselves to the eyes of any of our numerous party, 

 who were, nevertheless, highly gratified at the sight of so 

 brilliant and singular a creature." [Zool.Illust., vol. i.p. 43, 44.) 



I am, &c. 



G. J. 



P. S. — The compiler of these letters will feel particularly 

 indebted to any correspondent of this Magazine, who will 

 return him an answer to the following queries : — 



1. Ci/prada Tigris, " Mr. Samuel Stutchbury, who had 

 an opportunity of examining many individuals of C. Tigris 

 at the Pearl Islands, informed me that those cowries lived 

 there in very shallow water, and always under rolled masses 

 of madrepore. They never were to be seen exposed to the 

 sun's rays. On lifting one of those masses, a tiger cowry 

 was generally observed with its shell entirely covered by the 

 large mantle, which was mottled with dark colours, the in- 

 tensity of which the animal seemed to have the power of 

 changing ; for the colours varied in the same light and in the 

 same medium, after the manner of the spots on the cephalo- 

 podous mollusca, or, to use a more familiar instance, some- 

 what in the same way that the hues of a turkey-cock's wattle 

 vary." (Broderip in 2oo/. Jbwrw., vol. iv. p. 163.) The ques- 

 tion is. Does this change in colour, in the mantle of the 

 Cypr<^^« Tigris, depend on a structure of the skin, like that 

 of the Cephalopoda? 



2. The interior of the Fiisus antiquus is as yellow as the 

 yolk of an egg ; but the margin of the aperture, or, in other 

 words, the newly formed part of the shell, is white. Whence 

 is the yellow colour derived ? 



3. The apertures of Hehx cingenda and H. virgata are 

 generally tinted with a beautiful pink gloss, which, says 

 Mr. Jeffreys, is " entirely owing to the action of, and their 

 exposure to, the sun." (Lin. Trans., vol. xvi. p. 334.) But as 

 it is only on these species that the sun*s rays produce this 

 effect, it seems necessary to admit that there must be some- 

 thing peculiar to the shells or animals, on which the sun 

 operates this chemical change. What is this peculiar sub- 

 stance, and whence is it derived ? 



