308 North American Species of Zonites, etc. 
When first received, I beheved this to be an extremely globose 
form of Z. tnornatus, but an examination of the lingual denti- 
tion showed this to be impossible. 
On pl. XIV, fig. D, I have given a figure of the genitalia. It 
will be seen that the accessory part of the penis-sac is in this 
species continued to a point beyond the retractor-muscle : other- 
wise the genitalia are very similar to those of capnodes, friabilis, 
inornatus, laevigatus, and fuliginosus. The last species I find 
to have this accessory process also, though it is not given in 
Leidy’s figure. 
Jaw as usual in the genus. Lingual membrane (pl. XV, fig. I) 
as usual: teeth 38-1-38. There are about 4 or 5 laterals; the 
Sth is a pure marginal on either side of the central line. It will 
be seen in Terr. Moll. V, that tnornatus, subplanus and laevigatus 
are peculiar in having no perfect lateral teeth, but only transition 
teeth : faliginosus, capnodes, and friabilis, as well as Rugeli, 
have well formed laterals, differing in number in the various 
species : thus the lingual UEMULLION I in this group is a good guide 
in distinguishing the species. 
The animal is dark slate-colored : the caudal mucus-pore is a 
longitudinal slit as in swppressus (see Terr. Moll., V). 
Some individuals have their apicial whorls striate, as in 
4. subplanus. 
Zonites placentula, Shuttl. 
On pl. XV, fig. A, I give a figure of what appears to be the 
true placentula as described by Shuttleworth (whose description 
is translated in Moll., V, p. 124). The shell there figured, and 
also figured in this paper, pl. XV, fig. HK, is either a distinct 
species, or an elevated edentate form of lasmodon. 
Zonites Andrewsi, n. sp. 
On pl. XV, fig. D, is an illustration of a shell lately received 
from Mrs. G. Andrews, who collected it on Roan Mountain, 
Mitchell Co., N.C. It has the general appearance of 7. signifi- 
cans, multidentatus, and lasmodon, but differs so decidedly from 
each, that I propose to designate it by the name of its discoverer. 
A full specific description can be given later. Compared with 
