THE NAUTILUS. 51 
ious races of the modesta-series by means of variations in the 
number of teeth alone. It chances that the specimen chosen as 
type is one of the 3-toothed forms. 
The animal is bluish-gray or slate in color, the body quite 
dark, the foot and peripheral portions much lighter and semi- 
transparent. A rough sketch of the cephalic region of one of 
the Falls Creek specimens is offered in fig. 6. 
Whether the hereditary value of this race is that of a ‘‘ form”? 
or a subspecies can only be shown by the more detailed study 
which must be left for the future. Until then the personal 
equation must necessarily largely govern. In any case it will 
prove useful to have a name for it. 
VERTIGO ALLYNIANA New species. Fig. 7. 
The shell is minute, short, robust, ovate-conic in outline, 
thin, dark reddish-brown in color, with only a dull gloss; 
weakly, irregularly striate. The spire tapers with increasing 
rapidity from the last whorl to the obtuse apex. The whorls 
are convex, the last having a shallow but distinct excavation in 
the palatal region and a weaker one over the upper palatal tooth, 
the latter extending to the lip, which thus becomes flattened or 
very slightly indented on its outer segment. The aperture is 
pyriform in outline, and would be rather small except for the 
quite flaring lip, which is little thickened and very fragile at 
the edge. There are 5 teeth constantly developed in all the 
material examined. The parietal, columellar, and upper and 
lower palatal lamellae are well developed, and there is a distinct, 
though small angular lamella. The columellar is situated well 
back in the aperture and quite high up on the pillar. The 
lower palatal is also rather deeply immersed. 
Length of type 2.1; diameter to lip edge 1.3; length of aper- 
ture 0.81 mm.; whorls 4. 
Type: Cat. No. 3764 of the writer’s collection. Paratypes in 
the Academy of Natural Sciences of Philadelphia, and the 
private collection of Allyn G. Smith. 
Type Locality: Donner Lake, California; A. G. Smith, May 
30, 1916; 22 specimens. 
Remarks: I am not quite certain of the relationships of this 
