234 COLOUR OF MOLLUSCA. 



the Cypraea voluta of Montagu (Marginella voluta, Fleming) 

 has its fins or lateral expansions elegantly speckled with 

 bright yellow, and the fleshy part of its body with pink. * 

 The long proboscis of the Aporrhais pes-pelicani is pink, 

 dotted over with milk-white spots ; and the animal of the 

 white Scalaria clathrus is mottled black and white. Mr. 

 Collier says, of some tropical species, that the foot is " black- 

 ish red in the Murices generally; green in S trombus, and 

 some species of Trochus ; black in Bulla ovum ; deep red 

 with faint designs, like those of the shell, in Conus tulipa, 

 marmoreus, and its varieties ; spotted, in Buccinum harpa ; 

 bright yellow, in Buccinum cassis ; mottled, in Oliva ; and 

 deep brown, from spots, in some species of Voluta." f The 

 snail of the beautifully marbled Harp-shell (Harpa ventri- 

 cosa, Lamarck) glories in a rich vermilion red skin. " In 

 the Mauritius, it is the amusement of the place to watch 

 over the trim apparatus of lines hung over some sand-bank 

 to tempt the various brilliant species of Oliva which there 

 abound, or to wait for the more rare approach of the harp- 

 shell, till the rich hues of its inhabitant are seen glowing 

 through the clear blue water in the rays of a tropical rising 

 sun." J M. Rang has discovered that the animal of a spe- 

 cies of Sigaretus, described in the Bulletin of the Linnaean 

 Society of Bordeaux, changes its colour three or four times 

 during its life, — a circumstance which may easily lead to error, 

 by inducing observers to consider as distinct species what 

 are merely varieties dependent upon age ; and it appears 

 that Sigaretus is not a solitary instance of such mutability 

 among the Gasteropods. § 



The colours of the naked mollusca are very various : 

 there are black, white, grey, brown, yellow, red, and even 

 green species ; and the colours are sometimes uniform and 

 single, but more commonly mixed, and disposed in freckles 



* Montagu Test. Brit. p. 204. 



t Edinb. Phil. Journ. Oct. 1829, p. 228. Mr. Collier uses the Linnaean 

 names. 



J Broderip in Zool. Journ. ii. 199. " L'animal des Tridacnes et des 

 Hippopes offre de fort belles couleurs. Celui de la Tridacne safranee, decrit 

 parMM.Quoy et Gaimard, est d'un superbe bleu de roi sur les bords, line'ole 

 en travers de bleu de ciel ; plus en dedans est une rangee de lunules d'un 

 jaune verdatre ; le centre est d'un violet clair, avec des lignes longitudinales 

 ponctuees de brun. On a sous les yeux l'un des plus charmants spectacles 

 que Ton puisse voir, lorsque, par une petite profondeur, un grand nombre de 

 ces animaux ^talent le veloute de leurs brillantes couleurs, et varient les 

 nuances de ces parterres sous-marins. Comme on n'apercoit que leur ou- 

 verture baillante, on ne peut pas se figurer ce que c'est au premier aspect." 

 — Chknu Trait, de Conchyl. 87. 



§ Edinb. Journ. of Nat. and Geogr. Science, i. 455. 



