848 



were placet! apurt in different genera. Endeavouring, therefore, 

 to give a correct account of the species, and of course keeping 

 those most ahke, nearest to each other, I leave the task of form- 

 ing generic groups to those who think them useful. 



I wish to record my obligations to Mr. Arthur Adams, Surgeon, 

 ll.N,, for his kindness in permitting me the full use of his manu- 

 scripts on the present genus, of which he was preparing a mono- 

 graph. Had not that gentleman been called to the country before 

 the work was completed, my readers would have enjoyed the be- 

 nefit of his labours entire and unadulterated. As it is, having to 

 complete the work which he had begun, I have been forced, in a 

 measure, to model it upon my own views. It has nevertheless been 

 iny endeavour, as far as possible, to retain the same arrangements 

 which he proposed, although in another form; while the synonyms 

 so carefully collected in the manuscript have proved most valu- 

 able, and have in the great majority of instances been adopted as 

 ])erfectly correct. 



Division 1. — Marine, generally toith a produced canal. Oper- 

 culum oval, vnthfew wJwrls, 



1 a. A long, upturned canal, and a kind of plait or callus in 

 the middle of the columella. — Genus Yeiitagus, Klein, 



1. Cerithium Vertagus (pi. clxxvi. f. 2, 3), Linnmis, Syst. 

 Nat. (Murex). Vertagus vulgaris, Schum. 



Cerith. testa subcylindracea, albo vel pallide fulva, Iffivi; an- 

 fractibus superioribus nodulosim costatis, medianis latis, rectiuscu- 

 lis, ad suturam plerumque plicatis ; apertura obliqua, alba ; labio 

 intcrno crasso, biplicato; labio externo antice incrassato, canali 

 oblique recurvo. 



This common white or pale brown species has the central whorls 

 swelhng in bulk, although straight at the sides, and crenulated 

 or phcated at the sutures. From the Molluccas and Philippines. 



2. Cerithium tyeniatum (pi. clxxvi. f. 1), Quoy et Gaimard, 

 Voy. Astrolabe; Kieuer, Sp. Gen. Coq. pi, 19. f. 3. 



Cerith. testa C. Vertago simillima, sed rubro-fasciato canali bre- 

 viore. 



The form of the canal seems slightly different, being (from the 

 figure) shorter and less gradually curved than in 6'. / ertajns. 

 The colouring in bands, too, is scarcely a variation which we 

 should expect in the latter si)ccies. New Guinea. 



