250 Account of some new Vesuvian Minerals. 
the teeth. Our animal belongs to the former species, of 
which, portions of many individuals have been found on our 
continent, and a few, comparatively, in Europe. The beau- 
ty and value of these organic remains induced us to present 
them to the Lyceum of Natural History of New-York; and 
we have the satisfaction of knowing that they constitute an 
important addition to the fine collection ‘of fossils in the cabi- 
net of that valuable institution. 
ArT. VIIl.—Account of some new Vesuvian Minerals, by 
Sigg. Montice.ii and Covet. Translated by Dr- 
J. Van RENSSELAER. 
TO THE EDITOR. 
Dear Sir, . 
I sent you some time ago, a compressed account of the 
report on lightning-rods, made to the French Academy of 
Sciences, by M. M. Charles, Gay-Lussac, and de Romas, 
which you published in the 9th vol. of your valuable Journal. 
I have now the satisfaction to forward to you an account of 
some new Vesuvian minerals, which I have translated from the 
new work, in Italian, of Sigg. Monticelli and Covelli, of Naples, 
entitled, ‘* Prodromo della Mineralogia Vesuviana,” which 
they have kindly presented to me, together with a suite of the 
newly discovered substances. 
Very respectfully, yours, 
Jer: VAN RENSSELAER- 
February, 1826. 
N. B. The terms describing the varieties of the c I 
. rystals, 
are literally translated, and a to the plates of the original 
work—they are exhibited here in wood cuts. 
_ CLASS ITI. 
Species not yet classified, or altogether new. 
i BREISLAKITE. 
+ Pasifc characters. ; 
aed appearance of this singular species, is that of a brown- 
ish or reddish-brown down. Under the. microscope, it ap- 
