, 664 : General Notes. 
© crystals of different minerals from various localities. Gehmacher 
ives a series of measurements on the faces of colorless zire 
crystals from the Pfitschgrund, in the Tyrol. e axial ratio 
of datholite from the Seisser Alps, as calculated by Riechelmann, 
is a:b:c=0.63584:1:0.6329. The angle 2 = 89° 54’. The 
„new forms 4P, z,P, 4P?, 4;P;, $P3, and $P2(?) have been added — 
to the list of planes occurring on anatase 3 by Seligmann.——The 1 
same investigator has measured pyrrhotite from the druses of © 
basalt from the Cyclopean Islands. The results indicate that € 
the mineral crystallizes in the hexagonal system with the axial | 
ratio: 1: 1: 1: 1.65022,——In the same article Seligmann de f 
scribes a wolframite crystal from the Sierra Almagrera in Spain, — 
on which are the two new forms —2P? and —3P3. The mi 
gium. 
crystals from Vernasca, Italy, for the prismatic and end faces 
converge towards the free end of the axis to which they are par- 
allel, and along which the crystals have their greatest develop- 
; ment. É 
” 
| of the lava (with heat and pressure) on the carbonaceous S 
~ In contact with and enveloped by them. A study of the oc 
== tence of diamonds in other regions seems to indicate the 
_ rectness of this conclusion, as Mr. Diller? points out the fact 
Anson a oy xii. p. 50. -= Tb., p. 436. 
ee Dy ET 4Ib., p. 352. s Ib., . 
SH. C. Lewis, Geol. Magazine, January, 1887, p. 22, Ear ee 
n7 Science, Oct., OE i also Geol. Survey of Kentucky; Report © 
