Rev. L. Guilding's Mollusca CaribhcEana. 437 



In Ducks and Geese the base of this horny protuberance is 



very broad, in accordance with the breadth of the bill in this 



tribe of birds ; it also appears to have some relation in size to the 



thickness of the shell; in a preserved specimen of the young of 



the Egyptian Goose, taken from an egg within a few days of 



being hatched, this knob is particularly prominent, hard and 



sharp. 



I have the honour to be, 



Gentlemen, 



Your obedient servant, 



William Yarrell. 



Ryder Street, St. James's, 17th Oct. 1825. 



Art. XL VII. Mollusca Carihhceana. By the Rev. Lans- 

 Do\vx\ GuiLDiNG, B.A. F.L. Sf G.S. M.W.S., 8fc. 



Having found it impossible to draw up a satisfactory systematic 

 arrangement of the animals of this Subreg?ium, until 1 shall have 

 had opportunities of examining and dissecting specimens of many 

 genera which are but seldom obtained, I shall for the present 

 occupy myself in forwarding to the Conductors of the Zoological 

 Journal, accounts of such new or interesting subjects as I have 

 already met with ; intending at a future period to give a tabular 

 view of all our genera. 



The same difficulty exists with the 



Vertebraia,^ 



Annulosa, f /-. ., , 

 and i 



Radiata, ^ 

 but though no good arrangement can yet be offered, my AmcBni~ 

 tates Zoologicce and Crustacea Caribea will contain from time to 

 time figures and descriptions of such species as will be likely to 

 interest the Zoologist of Europe : at a future day they may ap- 

 pear in a more valuable form in a Fauna of the West Indiea, 



