154 Mr. G. B. Sowerby on the 



lato, lineis subprominulis cincto ; intiis roseo-violaced ; long. 2, hit. 



Bulla imperialis. Dillw. 



Ovula costellata. Lam., Ann. du Mus. XVI. 110. 



Hub. "Friendly Islands." G. Humphrey. 



Desc. Shell ovate, ventricose, milk-white ; the middle of the back 

 transversely obtusely angular, with a few raised lines ; the upper extre- 

 mity is not produced into a regular canal as in 0. Ovum, but the lower 

 canal is rather lengthened and truncated ; outer lip much thickened, cre- 

 nulated on its inner edge : inside of a delicate rose colour. 



I possess a dwarf variety of this beautiful species, which is of a 

 dirty brownish white on the back. It is observable that Lamarck has 

 very arbitrarily, and without giving any reason, changed the specific 

 name from costellata to angulosa ; I cannot help regretting this circum- 

 stance ; at the same time, I adopt the latter name as being the more ex- 

 pressive.* He states that this species is always smaller than 0. Ovum; 

 I have, however, some specimens of the latter that are full grown, and 

 yet smaller than the smallest I have seen of 0. angulosum. This is a 

 very rare species, and deservedly esteemed by collectors. 



OVULUM TRITICEUM, 



Lam., Anim. sans vert. VII. 368. 

 0. testa ovato-ohlongd, Icevi, rubro-aurantiacd ; labia externo albicante, 

 intus minutissime denticulato; columelld superne dente albido, valido, 

 subtii.s compressd; long. ^, lat. /q, jjoIL 

 Hab. . Mus. nost. 



Desc. Shell ovato-oblong, smooth, orange red; outer lip whitish, 

 rather straight-edged, slender, sloping from the outer to the inner edge, 

 which is very minutely denticulated ; there is a tubercular fold or strong 

 whitish tooth at the upper end of the columella, the base of which is 



♦ For the sake of avoiding an useless synonymy, it would have been desira- 

 ble to have retained Dillwyn's specific name of imperialis ; Lamarck has, how- 

 ever, in this instance, as in many others, been guilty of a great oversight in 

 describing as new a shell that had been described long before. 



