LOPHIODON MINIMUS. 315 
be a portion of the reserve-socket for the germ of the suc- 
ceeding molar tooth, of which there is no trace in the fossil. 
‘The tooth in question must therefore be regarded as 
a permanent premolar, and as the second in the series; 
and the fossil is accordingly proved to belong to a species 
of Lophiodon. The premolar (p g) bears the same pro- 
portion to the true molar (@ and 4), as the premolar of 
the larger species of Lophiodon exhibits in the entire se- 
ries of the lower jaw figured by Cuvier in the volume 
above cited, pl. i. Both teeth im fig. 108 belong to the 
same side of the lower jaw, most probably to the same 
lower jaw, and they offer no characters by which they can 
be distinguished from the Lophiodon minimus—the “ tres- 
petite espece dArgenton,” described by Cuvier in the 
volume cited at p. 194. 
In the posthumous edition of the ‘ Ossemens Fossiles,’ 
Svo. 1834, vol. 1. p. 362, a note is appended to the ar- 
ticle on the Lophiodons, in which M. de Basterot, ‘‘ jeune 
Naturaliste Anglais,” is cited as having maintained an 
opinion in a paper read to the “Société d’Histoire Na- 
turelle de Paris,” that the freshwater marls in central 
France, from which the remains of the Lophiodons had 
been derived, belonged to the formation of the plastic clay 
and lignite, which immediately succeed the chalk. 
The determination of the Lophiodon minimus im the 
plastic clay, overlying the chalk at Bracklesham on the 
Sussex coast, affords satisfactory confirmation of the high 
antiquity of the epoch of the tapiroid Pachyderms in the 
tertiary division of geological time. 
