STROMBIDA. 191 
When young, the outer lip of the shell is simple, resembling 
that of Strombus; the claws are gradually formed with the 
growth of the shell and are at first open canals, which afterwards 
become closed and solid. 
Messrs. Adams adopted two of Klein’s names for subgenera 
having no good characters; these may be advantageously re- 
placed by Prof. Theo. Gill’s arrangement, as follows: 
PTEROCERA, Lam. (restricted). Anterior canal straight or 
curved to the right, posterior canal ascending the spire. 
HARPAGO (Klein), H. and A. Adams. Anterior and posterior 
canals both curved to the left, the latter at first crossing trans- 
versely to the length of the shell. P. rugosa, Sowb. (lix, 63). 
PHYLLOCHEILUS, Gabb, 1868. (Malaptera, Piette, 1879.) Outer 
lip with no digitations, or small ones only; inner lip expanded 
as a thin plate over the front of the body-whorl, and sometimes 
projecting beyond it laterally ; both outer and inner lips deeply 
notched anteriorly, near the canal. P. speciosa, d’Orb. (1x, 74). 
RostreLLartA, Lam. 
Ltym.—Rostellum, a little beak. 
Syn.—Fusus, Humphr. Gladius, Klein. Platyoptera, Conr. 
Rostellum, Montf. 
Distr.—8 sp. Red Sea, India, Borneo, China. Range, 30 fms. 
R. curta, Sowb. (lix, 64). 
Animal with digitated mantle-margin. Operculum not serrated. 
Shell fusiform with elevated spire, whorls smooth ; aperture 
continued into a long, straight or slightly curved anterior canal ; 
outer lip slightly thickened on the margin and denticulated. 
The (restricted) Rostellarias belong to the present epoch, or 
extend at most only into the more recent tertiaries. 
HIPPOCHRENES, Montf. Posterior canal extending up the spire 
to near the apex, or curving behind it ; lip much expanded. An 
Eocene group; Europe and America. 2. macroptera, Lam. 
(dx 0.) 
RIMELLA, Agassiz. Whorls cancellated, posterior canal running 
up the spire, anterior canal short. Cretaceous—recent. Ke. Crts- 
pata, Sowb. (lix, 65 . 
LEIORHINUS, Gabb. | Fusiform, spire about as long as the 
aperture ; columella slightly twisted and with a fold or thick. 
ening on the edge, extending to the end of the canal ; inner lip 
thickened and with one tooth near the suture; outer lip thick- 
ened posterior to the edge ; edge thin and incurved, with a small 
emargination posteriorly, and opposite to the tooth on the inner 
lip; no anterior sinus; surface smooth or only marked by lines 
of growth. P. proruta, Conrad ‘Ix, 92). Eocene; Ala. Gabb 
placed it in Pleurotomide, but it was subsequently referred 
here by Conrad and Meek. 
