114 MURICIDA. 
Distr.—6 sp. EH. Africa. P. plumbea, Chemn. (xlv, 43). 
Fossil. Eocene of America and Europe. 
Shell ovate, solid, subglobose; spire very short, suture 
slightly channeled, whorls tumid round the upper part; aper- 
ture oval, canal very short; inner lip arcuated, with a callosity 
at the hind-part; outer lip thin, furnished at the fore-part with 
a small tooth or callosity. 
The shell has some resemblance to Monoceros in its tooth on 
the outer lip, and its operculum is purpuroid ; it also resembles 
the Olivancillariz. The animal is unknown. H. and A. Adams 
described a subgenus Macron, in which are included several 
species from the West Coast of America, but this group must be - 
eliminated, as the operculum has since been ascertained to be 
unguiculate. P. Australis is now placed among the Eburne as 
subgenus Zemira. 
Cnorts, Gray. 
Distr.—C. Belcheri, Hinds (xlv, 43, 44). Japan, California. 
Shell laminately varicose, spinose on the shoulder; canal 
rather long; outer lip with a spine as in Monoceros. 
To this group have been referred Ch. monoceros, Desh. 
(= Monoc. giganteum, Wesson), Ch. xanthostoma, Brod. 
(= Trophon), and Ch. Belcheri, Hinds. These three species 
are certainly representatives of three distinct genera, of which 
the last only remains to represent this genus. The dentition of 
Ch. Belcheri reminds one of the Buccinide more than any other 
group,and is nearest to that of the subfamily Photinew; but the 
shell does not bear out this relationship, its spines, peculiar 
varices and long canal suggesting Trophon, from which it is 
distinguished by having a purpuroid operculum and the tooth of 
a Monoceros. <A naturalist fond of making systematic groups 
might construct for this species a family, to follow, perhaps, 
Ptychatractide and intervening between the latter and Buc- 
cinide. In placing it between Monoceros and Pseudoliva and 
Rapana, I think that I have adopted the best alternative to the 
course above suggested. 
Prnaxia, A. Adams. 
Distr.—P. coronata, A. Ad. (xliv, 31). Polynesia. 
Shell conical; spire short, acute ; aperture oval-oblong, emar- 
ginate anteriorly; inner lip flattened, with several transverse 
plaits in the middle; outer lip acute, grooved internally. 
The shell has some resemblance to Pyrula pugilina in form as 
well as in the revolving raised lines within the aperture, but 
differs in possessing plications upon the columella. Mr. E. A. 
Smith has, fortunately, received specimens with the operculum 
in situ; this is purpuroid, and definitely settles the proper place 
of the genus. ‘The animal is unknown, and a description of it, 
