CYMRIUM. 79 



cluinneled shoulder and want of coroiiul spines. When fresh, 

 tlie epidermis is more or less covered by a thin glaze deposited 

 by the onvelopin*;- mantle. 



(i ray, Reeve and Sowerby have published monoii'raphs of tliis 

 genus ; the two latter with illustrations. For the figures of 

 Cymbium, Melo and Valuta, m the present work, I am mainly 

 indebted to Sowerby 's Thesaurus; they are usually much reduced 

 in size, but tlie dimensions of the species are indicated in my text. 



C. I'ROBOSCiDALE, Lam. PI. 22, figs. 1-4. 



Yellowish brown, or light salmon-color ; epidermis very thin, 



brown, over which the mantle of the animal deposits a thin glaze; 



columellar plaits four in the adult, of which the last is small. 



Length, 1 inch to a foot or more. 



W. Coast of Africa. 



C. x>orciniim, Lam. (figs. 3, 4) is the young of this species, 

 having only two columellar plaits, and the ends of the shell not 

 so attenuately contracted ; it has generally been distinguished as 

 a species with some doubt, but the specimens before me afford 

 good evidence of the gradual evolution oi proboacidale from por- 

 cinian. Between the glaze and the epidermis particles of sand 

 and even small organic bodies are frequently' imprisoned ; the 

 former giving the surface a minutely pustulate appearance. 



C. RUBiGiNOSUxM, Swains. PL 22, fig. 6. 



There is some little difference of form between this and the 

 last species, but I scarcel}' think them distinct. It was referred 

 to Australia b}^ Sowerby, and misunderstood and made a sj^non}' m 

 of C. cymbium (not of Linn) by Dr. Gra}^^ C. cisium, Lam. 

 Its true locality is N. W. Coast of Africa. Length, 4'5 inches. 



C. cisiUM, Lam. PI. 22, figs. 5, 7, 8. 



Shell light yellowish brown, elegantly marbled with chestnut. 



Length, 3-5 inches. 



W. Africa. 



Gray and others have referred C. cymbium, L.,to this species, 



but the evidence given b}' Mr. Reeve that the true C. cymbium 



= C. proboscidale is pretty conclusive.* C. gracile, Brod. 



(figs. 5, 8), appears to be a form of this shell. 



* Ann. Mag. N. Hist., 3d ser. vii, 271. 



