84 ARIONIDA. 
mucous pore; a distinct locomotive disk; exterior respiratory and 
anal orifices on the anterior right margin of the mantle ; orifice 
of the combined genital system below the last. 
Internal calcareous grains, in some species agglomerated, 
forming an imperfect shell- plate. 
Jaw ribbed Lingtial membrane with tricuspid central teeth, 
tricuspid or bicuspid laterals, and quadrate marginals. 
The ‘“ land-soles ” occasionally devour animal substances, such 
a dead worms or injured individuals of their own species. They 
lay 70-100 eggs between May and September, are 26-40 days 
hatching, and attain their full growth in a year; they begin to 
Oviposit a month or two before that period. The egos of A. 
hortensis are very phosphorescent for the first fifteen days 
(Bouchard). 
BAUDONIA, Mabille. Distinguished from Arion by being 
anteriorly enlarged and depressed, the shield almost smooth, 
the head well separated from the body, and the tentacles rather 
small. Characters of but little value. 2 Portuguese sp. 
ARIUNCULUS, Lessona, 1881. Genital orifice nearer the tentacle 
than the pulmonary orifice. 3 sp. A. Spezize, Lessona. Pied- 
mont. 
LOCHEA, Moquin-Tandon, 1855. Shell represented by unequal, 
isolated, calcareous granulations. A. rufus, Linn. Europe. 
PROLEPIS, Moquin-Tandon, 1855. Shell rugose, produced by 
the agoregation of separate calcareous particles. A. fuscus, 
Miill. Europe. 
ARIOLIMAX, Morch, 1860. 
Distr.—5 sp. Pacifie coast of United States. A. Columbianus, 
Gould (ci, 54). 
Animal limaciform, subcylindrical, tapering behind; tentacles 
simple; mantle anterior, small, concealing an internal shell- 
plate; longitudinal furrows above the margin of the foot, 
meeting over a caudal mucous pore; a distinct locomotive disk , 
external respiratory and anal orifices on the posterior right 
margin of the mantle; orifice of combined genital system on fhe 
right side of the body, below the anterior free edge of the mantle. 
Shell- plate internal, solid, flat, longer than wide. 
Jaw ribbed. Lingual membrane with tricuspid centrals, 
bicuspid laterals and quadrate marginals. 
Ariolimax differs from Prophysaon by the position of the 
respiratory orifice in the hinder half, and of the genital orifice 
below the free part of the shield, and the presence of a mucous 
pore. 
GromaLacus, Allman, 1843. 
Distr.—Eastern Europe. G. maculatus, Allm. (ci, 55). 
Animal limaciform, subcylindrical, blunt behind; tentacles 
