Mineralogy and Petrography. 349 
of these diabases are well worthy of the further study Mr. Lawson 
proposes to put upon them.—The Rev. E. Hill! mentions horn- 
blende schists from the island of Sark, in which he thinks he has 
found indications of a former bedding and evidences of sedimenta- 
tion.—Ternier? describes very briefly the eruptive rocks of the Mt. 
Mézeuc region in France, as presenting almost as great a diversity 
as those of Auvergne. They consist of augite and amphibole 
andesites, trachytes, phonolitic-trachytes and basalts in the order of 
their sequence. The basalts are the only ones which are at all 
widespread in their occurrence. 
MINERALOGICAL NEws.—New analyses of several rare minerals 
are communicated from the laboratory of the University of Vir- 
ginia. Mr. R. C. Price? found a lump of tscheffkinite, from Nelson 
county, Va., to possess the composition 2 R O. R, O,. 5(Si Ti), O,, 
in which R = Ca, Be, Fe, Mg, and R, = Ce, Di, La and Fe.’” 
Mr. Walker‘ obtained from genthite’ :— 
Si O, Ni O, Mg O H, O Fe, O; 
55.38 17.84 15.62 10.77 56 
corresponding to 4 H, O + 3 [(Mg Ni) OJ. Si O, + 4 H,O, a 
meerschaum (sepiolite) with its magnesium partly replaced by 
nickel. The mineral occurs in thin layers in a sandstone at Web- 
ster, Jackson county, N.C. It is amorphous, of a light apple- 
green color, translucent and greasy. It has a hardness of 2.5 an 
a specific gravity of 2.53.—Very similar to the last mentioned 
mineral is a nickeliferous talc, from the same locality, in which Mr. 
Bachman ê found :— 
Si O, NiO, Mro -Pao <Al,0, H,O 
53.91 15.91 19.39 46 2.65 6.30 
—Perimorphs of pyromorphite after cerussite and galena are men- 
tioned by Gonnard’ as occurring in the lead mines of the Puy-de- 
ôme, France. In some cases the pyromorphite exists merely as a 
thin shell enclosing a hollow space, from which the mineral for- 
merly occupying it has been removed by solutions—The same 
author describes a shell, composed of little rhombohedra of sider- 
i f a : “esp a" 
í Quart. Jour. Geol. Soc., Aug., 1887, p. 322. 
: Comptes Rendus, cv., 1887, p. 1141. 
Amer. Chem. Jour., Jan., 1888, x., p. 38. 
888, "> 44, 
: an., 1888, X., p. 45. 
1 Comptes Rendus, cy 1887, p 1267. 
, 1887, p. 227. 
