Recent Species of Ovulum, 159 



more so at the upper than at the lower ; back with a transverse raised 

 rounded angle rather above the middle ; aperture narrow at the upper 

 end, broader at the lower ; columellar lip with a single oblique plait close 

 to the upper end ; outer lip thickened, its inner edge smooth, without 

 teeth ; colour pale fulvous. 



I have named this intermedium, from the circumstance of the princi- 

 pal characters of two other species, namely the 0. gibbosum and O. bi- 

 rostre, being combined in it. I have seen only two specimens of this, 

 one of which is in Mrs. Mawe's, the other in my own collection. 



Ovulum birostre. 

 Lam., Anim. sans. vert. VII. 37Q. 

 O. testd, obhngd, ad utramque extremitatem rostratd, medio subventri- 

 cosd, lavissimd, albicante; aperturd supernk angustd, lineari, infrd 

 subeffusd; labio externa subtiis rotundato-angulato; coUumelld superne 

 obliquk unipUcatd; long. I^Vj ^«*' t%> P^^^' 

 Bulla birostris, nonnull. 

 Hob. ad littora Insularum Oceani Pacifici. Mus. nost., &c. 



Desc. Shell oblong, slightly ventricose in the middle, long pointed 

 at both extremities, very smooth, light coloured; upper end of the aper- 

 ture narrow, linear; lower end rather effuse; lower part of the outer 

 lip somewhat angular, angle rounded; a single oblique fold at the upper 

 end of the columella; outer lip more thickened in the middle than at 

 the extremities. 



Rather larger than Ovulum Spelta, from which it differs principally 

 in having both extremities produced in a lengthened point; how far this 

 character may be regarded as constituting a sufficient specific distinction 

 it is difficult to decide, particularly as there are specimens of interme- 

 diate character. I have thought it desirable to consider the short beaked 

 specimens as a variety of the present. Collections in general contain* 

 so few specimens of this interesting genus that I am obliged to form 

 nearly all my conclusions from the study of my own alimKt exclusively. 



* Very few collections contain more than seven of eight species, and La- 

 marck describes only twelve, whereas I possesa twenty-three, and have here 

 described twenty-five^ 



