> eer ee ae 
ye Aa 
6 age! a ey ee 
Say on Shells, &e. 4} 
Species. 
1. B, ovata, elongated; transverse septa subovate, sixlo- 
bed and a smaller one behind ; lobes of the superior faces of 
the septa, three on each side, with a minute one betwee 
each, dentated at their edges, anterior lobe, (nearest the 
siphunele) small not nevais second lobe with a single pro- 
jection each side and_ sinus at tip, third lobe dilated, with a 
small sinus each side and more obtuse and profound one at 
uP» posterior lobe hardly larger than the lateral intermedi- 
ones. 
gi a diameter of sie transverse section one inch and 
one fifth, smeiler diameter seven tenths; length of the seg- 
ment about an inc: Me 
The specimen isin B eelicelan, af Mr. Reuben Haines 
of this city, it was. found on the serena hills, in Mon- 
mouth County, New-Jersey, it is a east of three very entire 
segments, no-vestige of the shell remaining. The dimen- 
sions are taken from the largest segment. 
In point of form this species approaches B. vertebralis, 
Lam. particularly in the curvature of the transverse section 
but it is somewhat more obtuse behind ; another difference 
consists in the form of the lobes, which, in that species, as 
represented by Mr. Desmarest, are less symmetrical, des- 
titute of the lateral processes and of ea Pema terminal 
sinus; that species also is very dimin 
2. B, compressa, elongated, much ihe transverse 
septa oblong-oval narrowed to each end; lobes dilated, 
dentated on their edges, each ais from three to five si- 
nuses each side and a very profound. one at tip. 
This description is taken from two fragments in the col- 
lection of the Academy of Natural Sciences, which were 
brought from the Missouri, one by Messrs. Lewis and Clark 
and the other by Mr. Thomas Nuttall. As they exhibit the 
appearance of having been violently compressed by fortu- 
itous circumstances, I have not been able to obtain correct 
proportional dimensions of the species. But notwithstand- 
ing this distortion of form, I have much confidence in placing 
it next in specific affinity to B. Knorriana, Desm. as it | 
Wathen doubt been naturally a much compressed shell, ih 
sheseieral eg edges not very ualike “is of that large and 
on. IT.....No. 1. 
