1904.] NATURAL SCIENCES OF PHILADELPHIA. 419 
Thus the smallest adult is quite equal to the average recent shells. 
A few selected specimens of the fossil and recent shells can hardly be 
distinguished. Many of the fossils do not have the callosity. 
Locality 816 has great quantities of these shells so firmly cemented 
together that most of them are worthless as specimens. They have 
the peculiar spheroidal upper surface, but the perforation is wider 
than in the series from locality S0O8—not so wide, however, as in the 
recent. Several specimens here occur below some fragments of Pecilo- 
zonites nelsoni in stalagmite, apparently showing that they were there 
previous to the extinction of nelsoni. 
Broken and immature specimens from locality 808 show that the 
umbilicus was not much narrower than that of the recent variety until 
the last whorl had commenced to grow. The peculiar contour is also 
less noticeable prior to the last whorl. Thus in their smaller number of 
whorls, their less rounded contour, and their larger umbilicus, the 
present snails seem like an undeveloped or degenerate race of the 
former species. . 
It is possible that this fossil variety is what Pfeiffer (Monographia, 
I, p. 80) mistook for Helix ochroleuca Fer. 
Pecilozonites reinianus Pfr. 
Helix reiniana Pfeiffer, Malak. Bl., XI, 1863, p. 
P. reinianus Pilsbry, Proc. Acad. Nat. Sci. Pia, “1888, p. 290; 1889, p. 85, 
I found this species in every deposit eiaae except No. 807. 
Further search would doubtless show it there also. At locality 815 
many fine specimens were embedded in stalagmite. They show the 
typical color-pattern, with the dark marks changed as usual to reddish, 
and the lighter ground to ivory-yellow. 
The largest specimen from No. 815 measured.... Alt. 7 Diam. 13 mm. 
meetererest arom No, BOB 2.8 Nea cc lensecenigees 12 
Sees ssurem NpiS0G8). 228 iin Mu Oe ce 11.5 
The largest from the pocket at No. 814.........-2.0.----..-------2- 11 
The largest recent, lent by Mr. Bryant................ 6 11.3 
(nS SBT Ag) SS | re bese ee ee Seer ie ieee ee 5 10.3 
. From Town Hill (locality 819) come some good specimens of var. 
goodei Pils. Examples of these measure: 
Alt. 4 Diam. 10 Umb.4 mm. 
3.5 9.3 3.4 
ak 10 4 
The species is not so uniformly common as Pecilozonites circum- 
firmatus, but is very abundant in some places, for example, near 
locality 806. It would be interesting to learn whether its place in the 
economy of nature is different from that of the following species. 
