179 Jaw and Lingual Dentition of Pulmonaia. 
Helix Ayresiana, Newc. (Arionta). 
San Miguel Isl., California. Mr. H. Harford. 
Genitalia as in H. Traski (see Ann. Lyc. N. H. of N. Y., XI, 30, pl. 
vi, fig. 4). The flagellate extensions of the vaginal prostate beyond 
the bulbs in this species are, however, much shorter and stouter. 
Helix exarata, Pfr. (Arionia). 
Alameda Co., Calfornia. Dr. L. G. Yates. 
Genitalia as in H. Nickliniana, Proc. Ac. Nat. Sc. Phila., 1874, pl. iv, 
fig. 3. 
Helix Diabloensis, J. G. Cooper. (Arionta). 
Alameda Co., California. Mr. L. G. Yates. 
Jaw as usual in the genus, (see Proc. Phila. Ac. Nat. Sc., 1875, 216), 
with 5 ribs. 
Lingual membrane (pl. xv, fig. G), as usual in the subgenus. The 
central and first lateral teeth have no side cusps or cutting points; these 
appear on the 18th tooth. The 18th tooth has its inner cusp bifid; there 
may, therefore, be said to be 17 laterals. The marginals (see figure for 
the last one), are low, wide, with one inner, long, oblique, bifid cutting 
point, and one outer small cutting point. There are 37-1-37 teeth. 
Genitalia as in H. exarata. 
Helix arrosa, Gould (Arionta). 
Plate xii, fig. 5, gives the genital system. 
The penis-sac is extremely long and gradually tapers into a flagellum. 
It receives the retractor muscle beyond the middle of its length, and the 
vas deferens at three-quarters of its length from the vagina. The genital 
bladder (g. b.) is very small, oval, on a very long duct, which has a very 
long, stouter, accessory duct (a. d.). 
From H. Nickliniana, H. arrosa differs greatly in the total want of the 
peculiar accessory organ, probably a vaginal prostate, which characterizes 
that species (see Phila. Proc. 1874, 41, pl. iii, fig. 4). From H. Town- 
sendiana, it still more widely differs (see same, 1873, 254, pl. i, fig. 4), in the 
character of the penis-sac and genital bladder. 
Helix facta, Newc. (Arionta). 
Sta. Barbara Island, California. Mr. H. Hemphill. 
In my account of the dentition of North American Land Shells in Proc. 
Phila. Ac. Nat. Sc., 1875, I was unable to include this species. 
