NATURAL SCIENCES OF PHILADELPHIA. 175 
50 teeth, with 18 perfect laterals. The centrals have a much more 
graceful outline to the reflection than in the two last-named 
species. The median cusp is longer and more slender, with a more 
slender cutting point ; the subobsolete side cusps are more marked, 
and hear well developed, triangular, slightly curved cutting points. 
The lateral teeth are like the centrals, but unsymmetrical by the 
suppression of the inner lateral lower expansion of the base of 
attachment. There is, however, an inner cutting point lying 
against the inner side of the cusp, rather than in a position cor- 
responding to the outer cutting point; it is very difficult of de- 
tection, being on a different plane from the outer cutting point, 
and readily confounded with the inner lower angle of the base of 
attachment. It is figured by Lehmann and Heynemann. The 
marginals are long and slender, without bifurcation even on those 
on the extreme edge of the membrane. Fig. 105 of p. 63 of L. 
and Frw. Shells N. A. I., probably was drawn from a specimen 
of this species, certainly not from one of flavus. 
Goldfuss (1. ¢. pl. V., fig. 4) omits the cutting points from his 
figure. | 
Limax Hewstoni, J. G. Cooper (pl. IV., fig. 2). The centrals 
and laterals are of the same type as in the last species, with this 
important difference, that there is a well-developed cutting point 
of the usual form (not the peculiar form as in Z. agrestis) to the 
inner subobsolete cusp of the laterals, and the inner lower lateral 
expansion of the base of attachment of the laterals is not sup- 
pressed as usual to make the laterals unsymmetrical. From this 
it follows that the central teeth are with difficulty distinguished 
from the laterals, until the outer ones are reached, when the inner 
cutting point and inner lower lateral expansion of the base of 
attachment are suppressed as in the other species of Limax. The 
marginal teeth are not bifid. Teeth 30—1—30, with 14 perfect 
laterals. Fig. b represents the very last marginals. As in the 
membranes of almost all species of land shells, there is consider- 
able difference in the marginals on different portions of the same 
membrane. ‘Those figured are the least slender. 
This species, by the presence of the inner cutting point of the 
laterals and non-bifurcation of the marginals, resembles Limax 
(Amalia) gagates, as figured by Semper (Phil. Archip., pl. XI.), and 
nutida Mollusker, pl. I., fig. 3), disagrees with my observation by the bifur- 
cation, of the marginals. 
