Miscellanies. 379 



mensions at Maria Island, is still more degraded at the Island of 

 Decres and Josephine, is only a miserable abortion on the rocks of 

 Nuytland, and is no longer visible at port King George. The same 

 thing is observable in the Phasianellus ; their proper habitation is at 

 Maria island where vessels are loaded with them ; and after siifFering 

 insensible degradations they are lost at port King George. It is in- 

 teresting to witness the same phenomena exhibited in a horizontal 

 direction on the present surface of the earth, appearing again in a 

 vertical direction upon the different surfaces, which, at successive 

 periods have limited the exterior configurations of the terrestrial 

 globe. — Bib. Univ. Bee. 1830. 



3. JVLonography of the genus Cyprcsa. — Dumeril and De Blain- 

 ville made a report to the Academy on the 27th of December, on 

 the memoir of M. Duclos, entitled Monographie du genre Cyprcea, 

 (vulgairement coquilles porcelaines.) This kind of shells is one of 

 those for which amateurs have still a predilection, not only on ac- 

 count of the elegant and singular form of the shell, but especially 

 from the beauty of their robes, the almost infinite variety of the col- 

 ors with which they are ornamented, and of the splendid kind of 

 varnish with which they are covered. It is in this genus therefore, 

 as well as the cones and volutes, that are included those species 

 which have retained the greatest venal value. It is time that this 

 genus,, which has long been only an object of luxury and curiosi- 

 ty, should rise to a level with the other departments of concJiology. 

 This was not an easy thing, on account of the connection between 

 the animal and its shell, and of the peculiar developement of the 

 lobes of its mantle, which, void in its earliest period, acquires a 

 successive developement, so as to cover the entire shell when the 

 animal is at rest. The shell passes through three or four distinct 

 stages, which are very different in form, and especially so in struc- 

 ture, thickness and color. Several naturalists, with a view to an ex- 

 planation of the fact, that in the same species there are found both 

 dwarfs and giants, have thought it suflicient to state that the animal 

 changed its shell, an opinion which appears to the reporters to have 

 been victoriously refuted. The labors of Lamarck, de Blainville, 

 and of Gray, adjunct curator of the British Museum, have still left, 

 much to be desired. M. Duclos has been perseveringly engaged for 

 fifteen years in the monography of the genus Cyprcea. During his 

 travels in Belgium, Holland and England, he has acquired new ma- 



