MUSEUM OF COMPARATIVE ZOOLOGY. 365 
Hemphillia, Bu. & Bryn. Animal limaciform, blunt before, swollen at 
centre, and greatly attenuated behind : tentacles simple : mantle subcentral, 
large, oval, concealing all but a rounded. large orifice, an internal shell-plate : 
longitudinal furrows above the margin of the foot and caudal mucus pore, over 
which is a hump-like process : no distinct locomotive disk : external respiratory 
and anal orifices at the central right margin of the mantle: orifice of combined 
genital system near the right eye-peduncle. 
Shell-plate horny, small, unguiform, longer than wide, with posterior nucleus 
and concentric lines of growth. 
Jaw ribbed. 
Lingual membrane with tricuspid central teeth, bicuspid laterals, and quad- 
rate marginals, 
Coast of Oregon. 
The swollen central portion of the animal seems the first approach to a turbi- 
nate mass of viscera, separated from the foot. 
Geomalacus, Arm. Animal limaciform, subcylindrical, blunt behind: 
tentacles simple: mantle anterior, close to head, concealing a shell-plate : lon- 
gitudinal furrows above the margin of the foot? a caudal mucus pore : a dis- 
tinct locomotive disk: external respiratory and anal orifices on the right far 
anterior margin of mantle : orifice of combined genital system behind and 
below right eye-peduncle. 
Shell-plate calcareous, flat, small, internal, ovate. 
Jaw ribbed. 
Lingual membrane with tricuspid centrals, bicuspid laterals, quadrate mar- 
ginals, 
Eastern Europe. 
For figure of the animal and internal shell plate, see Adams’s Genera ; of 
jaw and lingual dentition, see Heynemann, Malak, Blatt, XXI., Nachr, der 
Malak, Gesell., T. 165, PL I. 
Letourneuxia, Boura. Animal limaciform, subcylindrical, scarcely atten- 
uated behind : tentacles simple: mantle small, anterior, concealing a shell- 
plate : no longitudinal furrows above the margin of the foot, and no caudal 
mucus pore; no distinct locomotive disk: external respiratory and anal orifices 
on the right anterior margin of the mantle : orifice of combined genital system ? 
Shell-plate internal, calcareous, suboval, flat. 
Jaw ribbed. 
Lingual membrane ? 
Algiers, 
There is a peculiar overhanging process to the side of the body, near the tail. 
For figure of animal, internal shell-plate, and jaw, see Bourgignat, Moll. 
Nouv., VIL 1866, p. 201, Pl, XXXIV. Fig. 7. 
Peltella  WxnB $ Van Bun. (Pectella, Gray.) Animal limaciform, 
rounded above, flat below, sides widely expanded : tentacles simple : mantle 
