1905.] NATURAL SCIENCES OF PHILADELPHIA. 243 
Alt. 5.3, diam. 12 mm. 
Repo 1 BRS fF 
aor EN) RO 
Chiricahua Mountains, Sawmill Canyon. Types No. 86,498, A. N. 
S. P., collected by James H. Ferriss. 
Less carinated than the closely related A. fissidens which is appa- 
rently a member of the same series. It is difficult to decide on the rank 
to be given to the members of these chains of modifications of a single 
type. A. proxima will probably be considered a species eventually. 
There are 14.10.1.10.14 teeth. The side cusps are very short, almost 
subobsolete on the central teeth. The tenth to twelfth teeth are tran- 
sitional. Both cusps are split on the marginal teeth. 
The genitalia (Pl. XXI, fig. 24) of one of the type specimens figured 
has the atrium protruded. There seems to be an extremely short 
basal enlargement or penis in another individualopened. The retractor 
muscle of the penis is very weak. The proportions of the organs are 
given in the table on p, 224. The very short penis contrasts with A. l. 
angigyra, which also has more marginal teeth. 
The jaw (Pl. XXIII, fig. 17) is thin, with about 5 ribs, of which only 
two are well developed. 
Ashmunella fissidens n.sp. Pl. XIV, figs. 67-69. 
Shell depressed, lens-shaped, biconvex, with acutely angular pertph- 
ery; rather thin, brown. Sculptured with fine, irregular growth-lines, 
the penultimate and next earlier whorls more or less roughened with 
minute elevated points, as in A. angulata. Spire very low conoid. 
Whorls fully 6, closely coiled, moderately convex, the last usually a 
little impressed above the periphery, which is angular throughout. It 
is convex below, and deeply guttered behind the reflexed outer and 
basal margins of the lip. The suture descends a little to the aperture. 
The aperture is very oblique, much obstructed by four teeth; an oblique 
parietal lamella, curved in at its axial end, with, in old specimens, a very 
low converging ridge outside of it, the two arranged V-like; a long, 
Square-topped or concave-topped tooth within the outer lip; and two 
contiguous teeth on the basal lip, slightly united basally the outer one 
thick and higher, the inner low and more spreading. Parictal callous 
distinct. 
Alt. 5.3, diam. 12.3 mm. 
éc 5, 7 11.5 “ 
ire eae 
Chiricahua Mountains, in Cave Creek Canyon. Types No. 87,022, 
A. N.S. P., collected by James H. Ferriss, February, 1904. 
