VITRINIDA. 21 
Virtrinozonites, Binney. 
Distr.— V. latissima, Lewis. Tennessee. 
Shell like Vitrina. Animal having a caudal mucous pore with 
longitudinal furrow ; no appendiculate mantle-process; marginal 
teeth of radula simple, not bifid. 
VELIFERA, Binney. 
Distr.—V. Gabbi, Binney. Costa Rica. 
Shell as in Helicarion. Animal: mantle with one or more 
accessory processes which cover most of the shell; a simple 
longitudinal mucous pore, without horn-shaped process; jaw 
with smooth anterior surface, and beak-like projection on the 
cutting edge; radula resembling Zonites. 
PARMELLA, H. Adams, 1867. 
Distr.—P. planata, H. Ad. (xcii, 79). Fiji Isles. 
Animal undescribed. Shell depressed, spire flat, epidermis 
horny, polished, extending greatly beyond the posterior part of 
the margin. 
VITRINOIDEA, Semper, 1873. 
Distr.—V. Albaiensis, Semper. Philippines. 
Shell wholly concealed by the mantle, with cuticle and cal- 
careous layer, forming several whorls; respiratory orifice before 
the middle of the mantle; no caudal mucous pore; marginal 
teeth of the radula three-pointed ; jaw smooth; accessory glands 
at the genital organs ; no flagellum. 
VitTRINopsis, Semper, 1872. 
Distr.—2 sp. Philippines. V. tuberculata, Semper. 
Two lobes of the mantle covering a part of the shell in front 
and on the left side, not on the right as in Vitrina. Lateral 
teeth of the radula three-pointed, not 1—2 pointed as in Vitrina. 
VitTRINOcCONUS, Semper, 1873. 
Distr.—9 sp. Philippines. JV. cyathus, Pfeiffer. 
Shell umbilicated, conical or trochiform, apex obtuse ; whorls 
planulate, the periphery carinate or angulate; aperture lunate; 
peristome simple, acute or thickened. 
Mantle sometimes with cervical lobes, but no shell-lobe ; 
lateral teeth of the radula two-pointed. 
Laconia, Gray, 1855. 
Disir.—1 sp. L. Ferussaci, Gray. 
Body subglobose ; mantle edged, produced in front, forming a 
broad collar. 
Shell subglobose, entirely and permanently covered by a thin 
expansion of the mantle; spire of few whorls, the last very large ; 
aperture very large, lunate. 
