114 3 [J UNE, 
or whether it is peculiar to that from California, | treated some from the Oural 
Mountains in-the same manner, and found that most, but not all of the lead- 
colored scaJes are oxydized and assume yellow, orange and blue colors. ‘This 
reaction seems therefore to be an important one to distinguish Sisserskite from 
Newjanskite. It is very likely, too, that we find in nature but two combinations 
of Iridium and Osmium, Ir Os and Ir Osa and that Ir-Os3 is Ir Os4 mixed with - 
some Ir Os, as it is very difficult to distinguish their color. 
On Strontiano-calcte, a New Mineral. 
By Dr. F. A. Genta. 
Primitive form an obtuse rhombohedron (as it seems to show cleavage parallel 
to the planes of a rhombohedron, similar to that of calcite); the secondary forms 
which I observed were the second acute rhombohedron (analogous to that of 
calcite of 65° 50’) and its corresponding scalene-dodecahedron. Crystals micros- 
copic and not very distinct; in globular masses formed by an aggregate of rliom- 
bohedrons, every globule terminating in the above-mentioned acute thombohe- 
dron. Fracture uneven. H. = 3.5. Sp. gr. = ? 
Colorless and transparent at the points of the aggregations, which are white 
and translucent. The colorless crystals have a vitreous, the white ones a some- 
what pearly lustre. 
When heated before the blowpipe it gives out a brilliant light, imparts to the 
flame a slight crimson color, and is rendered caustic. Easily soluble in acids 
with disengazement of carbonic acid. The solution gives a white precipitate 
with sulphate of lime, but not with sulphate of strontia; it therefore contains 
strontia. After, (in another quantity of the solution,) strontia was precipitated 
with sulphate of potash, the addition of oxalate of ammonia produced a precipi- 
tate of oxalate of lime. 
The quantities I had at my disposal were too small to admit of a quantitative 
analysis, but I presume from the quantities, precipitated with sulphate of potash 
and oxalate of ammonie, that lime and strontia are contained in Strontiano-calcite 
in about equal proportions. 
The specimen was presented to me by William Wagner, Esq., who collected 
it in the neighborhood of Girgenti in Sicily, where it, according to his statement, 
is of rare occurrence and associated with celestine and sulphur. 
In the chemico-mineralogical system it is to be placed between Dufrenoy’s 
Dreelite and Plumbocalcite. 
Of the carbonates which have isomorphous bases, of carbonate of lime only, 
two forms, rhombohedron and rhombic prism, have been observed; of carbonate 
of lead, strontia and baryta, only the rhombic form is known; but when in com- 
bination with carbonate of lime, they all likewise crystallize in the rhombohe- 
drical form, thus forming Plumbo-calcite, Strontiano-calcite and Dreelite. It is 
very likely, that we one of these days will meet with rhombohedrical forms of 
the pure carbonates of lead, strontia and baryta. 
The Committee on a paper by Messrs. Audubon and Bachman, read 
this evening by special permission, describmg a new species of North 
American Fox, reported in favor of publication : 
Description of a new North American Fox. Genus Veelvess © Cw. 
By AvupusBon anp BacuMaNn. 
Vubres Utan. 
V. corpore grandiore, pilis velleris longioribus nec non gracilioribus quam in 
V. fulvo, cauda magna cylindracea. 
Speetfie characters. —-Larger than Vulpes fulvis; fur longer and finer than in 
that species; tail large and ‘cylindrical. 
