Great Aurora of 1859, 249 
length of the valve towards the front, the cardinal edge being 
evelled off from the apex to the hinge line. The lines of 
growth are prominent along this bevelled edge; so they are too 
on the cardinal area of the large valve. 
| - The external surface of C. Americana is obscurely marked 
longitudinally in front by strie, which, so far as they have been 
_ “il are coarser and less numerous than in C. sandalina, 
There are other points of difference which appear to be con- 
mo but those given are sufficient to characterize the species. 
a future occasion the fossil will be illustrated by the proper 
Tebanon, Tenn, Feb. 1, 1860. 
; Atl. XXIV —The Great Auroral Exhibition of August 28th to 
September 4th, 1859.—3p ARTICLE. 
Pd the two preceding numbers of this Journal* we have given 
Tvations of the Aurora of Aug. 28th to Sept. 4th, from nu- 
of the pe in North America. We now continue our record 
Sent a sy . 
~ We are indebted to Mr. Benj. V. Marsh, of Philadel- 
Dhia, for : 
2 Observations at Montreal (lat. 45° 81’), by Dr. ARCHIBALD Hatt. 
tejtlgust 28th about 8h 20m p,m. the sky was about seven 
hee” obscured b massive cumuli, when in the interval between 
I observed” streamers of a ruddy tint passing from the 
‘1 towards the zenith. The wind was N.N.W. and blowing 
Scop * Vols. xxviii, p. 385; xxix, p. 92. 
SERIES, Vor. XXIX, No. 86,—MARCH, 1860. 
32 
