1104 General Notes. 
exterior of the valves; dental lamelle in ventral valve slightly 
produced, sloping abruptly backward and downward, becoming 
obsolete before reaching the center of the valve; cardinal processes 
of dorsal valve small, bifid, fitting into notches in area of ventral 
valve. 
This is one of the most variable species of Spirifers known to me. 
The descriptions of this species, and Spirifera hungerfordi, are 
based upon over one hundred and fifty specimens of each species.— 
Position and locality: Rockford Shales, Rockford and Hackberry, 
and Owens Grove, Iowa. 
There seems to be no doubt but that this very variable species 
(designated as Spirifera orestes, by H. & W..,) is identical with 
Spirifera strigosa Meek, as described in Vol. IV., p. 43, of the 
. S. Geol. Exploration of Fortieth Parallel. This being the 
case, Meek’s name would, therefore, be considered as having the 
priority. : 
Atrypa hystrix var. elongata, n. var.—Shell of medium size, 
elongate ovate, valves slightly aud nearly equally convex; 
greatest convexity of the ventral valve slightly below the 
umbo; greatest convexity of the dorsal valve on the umob. 
ak of the ventral valve of moderate strength, perforate, 
scarcely raised above the opposite valve; area closed, surfaces 
marked by from four to five simple rounded ridges upon each valve, 
crossed by strong thickened concentric lamine of growth, but 
which are nut elevated at intervals into spine-like protections. This 
well-marked variety is known to occur at only one locality, the 
Rockford Shales, at Hackberry, Iowa. j 
Atrypa hystrix var. planosulcata, n. var.— This form differs from 
A. hystrix in the general expression and fineness of the shell. The 
plications are very much smaller and more numerous, the lamine 
of growth usually slight and not generally elevated into spine-like 
projections. These features are very constant in both young an 
old specimens. i 
We were at first inclined to consider this form specifically dis- 
tinct from A hystriæ, but after a large number of them had b 
secured, it proved that they constituted only a well-marked variety 
of this species. ; 
This variety is common throughout the Rockford Shales, and se 
also the prevailing form which occurs in the limestone which imme- 
diately underjliesthe shales. We have also secured a very few x. 
imens from some shales at Roberts’ Ferry, Solon and Turkey 
Creek, in Johnson county.—Clement L. Webster. 
_ Caves anD Cave Lire.—There are a few statements made in Dr- 
<. Packard’s article in the September number of the AMERICAN NATU- 
o BALIST, which, while they do not affect the argument, seem to 
