THE NAUTILUS. 13 
shells. The surface is usually destitute of spiral sculpture, 
only a few faint impressions being observable in rare specimens. 
One individual, however, had been injured when the body 
whorl was about half completed and the part of the shell suc- 
ceeding the injured portion is very heavily impressed with spiral 
lines, while the rest of the shell is perfectly smooth. 
This shell was first recorded from Tomahawk Lake, Wis- 
consin, as Physa ancillaria warreniana. The same form occurs 
in Lake Maxinkuckee, Indiana, on the shore of Lake Michigan 
at Chicago, and a somewhat similar form has been received 
from Georgian Bay, Canada. It is the most abundant mollusk 
in Oneida Lake where it oceurs on a wave-beaten shore. It is 
probably widely distributed, and will be found in collections 
labeled ancillaria and heterostropha. Specimens that have sur- 
vived a second year and are of large size compare favorably with 
warreniana but may at once be separated by the absence of spiral 
sculpture which is especially strong in shells of Lea’s species 
from South Dakota and other western states. 
The bibliography of the new species is as follows: 
1902. Physa heterostropha Baker (non Say). Moll. Chicago 
Area, Part II, p. 308, pl. 34, fig. 2 (part). Lake 
Michigan. 
1911. Physa ancillaria warreniana Baker (non Lea). Trans. 
Wis. Acad. Arts, Sci. and Letters, XVII, p. 234. Tom- 
ahawk Lake, Wis. 
1916. Physa ancillaria warreniana. Navtitus, XXX, p. 8. 
Oneida Lake, N. Y. 
1916. Physa ancillaria warreniana. Tech. Pub., N. Y. State 
Coll. For., Syracuse Univ., No. 4, p. 278, et seq., Fig. 
45, nos. 34, 35. Oneida Lake. 
1918. Physa warreniana. Navtitus, XXXI, p. 89. Oneida 
Lake. 
1918. Physa warreniana. Tech. Pub., N. Y. State Coll. For- 
estry, No. 9, p. 173, et seg. Oneida Lake. 
