192 STROMBID. 
ISOPLEURA, Meek. Longitudinally ribbed, aperture narrow, 
notched in front, outer lip simple, no posterior canal. Cretaceous. 
R. curvilirata, Conr. (1x, 76). 
cycLoMoLops, Gabb. Smooth, without anterior canal, posterior 
canal long, running up the spire, columellar lip with a thick 
callus which, continuing around the anterior end of the aperture, 
forms a thickened margin to the outer lip. R&R. levigata, Mellv. 
d=): 
ORTHAULAX, Gabb. Shell rounded-fusiform, canal moderate, 
straight and regularly tapering; adult shell enveloped over the 
whole spire by an extension of the inner-lip callus; posterior 
canal fissure-like, formed by the continued edge of the outer lip 
and running directly to the apex; outer lip apparently sharp 
and simple, anterior notch oblique and broad. P. inornata, 
Gabb. Tertiary ; West Indies. 
CALYPTRAPHORUS, Conr. Anterior canal long and straight ; 
posterior canal long, appressed to the spire and arching on the 
back ; outer lip moderate, rounded and thickened on the margin 
by a smooth border; young shell showing all the volutions, 
which are hidden in the adult by a polished incrustation covering 
the entire surface, and in some species bearing tubercles. 
Eocene; U. 8. Cretaceous; India. &. trinodiferus, Conr. 
Cio): 
SPINIGERA, d’Orb 
Distr.—5 sp. Fossil, in the Oolite of Europe. 8S. longispina, 
Desl. (Ix, 79). S. spinosa, Munst. (1x, 80). 
Shell elongated, slender, fusiform, with a long, straight 
anterior canal; each volution bearing one or two varices, those 
of successive whorls being arranged continuously as in Ranella, 
and bearing each a long, transverse spine. 
TEREBELLUM, Lam. 
Htym.—Diminutive of terebra, an auger. 
Syn.—Seraphs, Montf. 
Distr.— T. subulatum, Lam. (lix, 66). China, Philippines. 
Fossil, 8 sp. Eocene—; London, Paris. 
Animal with eyes on the ends of peduncles, no tentacles, foot 
anteriorly small and rudimentary. Opereculum narrow, denticu- 
late. Shell subulate, spire slightly produced or blunt ; aperture 
narrow, notched in front; outer lip simple, sharp; inner lip 
more or less incrusted, the columella straight and truncate. 
The Terebellum inhabits deep water. In progressing, it 
rolls its shell over and over, performing a series of irregular 
jumps; when first taken from the water, it will even leap several 
inches from the ground. It is extremely shy and sensitive in 
its habits, poising the shell in a vertical position, and protruding 
the longer telescope eye (for, singularly enough, one eye-pedicel 
