FOSSILS OF THE CARBONIFEROUS. 261 
Genus AMPULLARIA Lamarck. 
Ampullaria ? Powelli Walcott. 
Ampullaria ? Powelli Walcott, 1883. Science, vol. ii, p. 808, figs. 3, 3a. 
Shell subglobose; umbilicus small; spire depressed; volutions three or 
four, increasing uniformly in size until the last one, which is larger in pro- 
portion and slightly expanded at the aperture; suture dis- 
tinct; aperture oblong, broad ovate, and a little straightened 
on the inner side, entire; peristome continuous, slightly 
reflexed. 
Surface marked by fine lines of growth. Operculum ; 
Fie. 4.— Outline 
figure of a typi- 
cal shell, X 3. 
concentric, rather thick, and of a calcareous or shelly struct- 
ure; nucleus subcentral. 
In referring this species to the genus Ampullaria we 
bear in mind that it is not probable that a genus of this 6) 
character has continued from the Middle Paleozoic to the ——_ 
present time; on the other hand, when we consider that the a ieee 
shell is Ampullaria-like in character and associated with an operculum that 
is almost characteristic of the genus, that the’ genus Pupa is known from 
the Middle Carboniferous, and that a shell not to be distinguished from . 
the recent Physa is associated with Ampullaria? Powell, a pulmonif- 
erous shell Zaptychius Carbonaria and a twig of a coniferous tree, all of 
which are evidences of a near land area, it would appear that a reference 
to Ampullaria, as the genus representing the group to which the species 
belongs is warranted by the facts, although it may be ultimately referred to 
a new genus or subgenus. 
Formation and localities —Lower portion of the Carboniferous Group, 
on the western slopes of New York and Richmond Mountains, Eureka Dis- 
trict, Nevada. 
PULMONIFERA. 
For an excellent summary of what was known of the Paleozoic rep- 
resentatives of this subclass up to the month of November, 1880, we are 
indebted to Dr. J. W. Dawson, who states that the three known localities of 
their occurrence are on the American continent, and that six species were 
