154 Mr. G. B. Sowerby on the 



latOf lineis subprominulis cincto ; intiis roseO'violaced ; long, 2, lat. 



Bulla imperialis. Dillw, 



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



JZa6. "Friendly Islands.'* G, Humphrey, 



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

 transversely obtusely angular, vi'iih. a few raised lines ; the upper extre- 

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

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

 milated 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 O, angulosum. This is a 

 very rare species, and deservedly esteemed by collectors. 



OVULUM TRITICEUM, 



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

 O, testd ovato-oblongd, Icevi, rubro-aurantiacd ; labio externo albicante, 

 intus minutissimd denticulato; columelld supernk dente albido, valido, 

 subtiis compressd; long. ^^, lat. /^, poll. 

 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. 



