1886. | Mineralogy and Petrography. 161 
yellow grains, chloritized biotite, dark-green hornblende, clear 
transparent orthoclase and microcline and opaque altered plagio- 
‘clase in a groundmass of small brown plates of biotite and clear 
orthoclase and quartz in micropegmatitic growths. Pilite-kersan- 
tite from Spitz on the Donau and pyroxene-amphibolite from 
Aschauer are also described. In the same article Becke reports 
the result of a reinvestigation of Schrauf’s kelyphite,' the altera- 
tion product of pyrope in olivine rocks. This substance, he 
thinks, is a mixture of a chrome-spinel and a ‘silicate, probably 
hornblende. The reaction of the olivine on the garnet he rep- 
resents thus: : 
Mg,Al,Si,0,. + Mg,SiO, = Al,MgO, + Mg,Si,Qj, 
rope, in spinel, amphibole. 
—lIn a letter to the Neues Jahrbuch, F. H. Hatch describes 
hypersthene andesite from Mt. Chachani, in Peru. Inclusions 
of mica-schist, marble and syenite are .mentioned® by Hussak as _ 
occurring in the phonolite of Oberschaffhausen. The same 
writer* denies the widespread existence of cordierite in Hunga- 
rian andesites, but finds it in many trachytes. Kolenko® men- 
tions hornblende pseudomorphs after olivine as characteristic of a 
metamorphosed olivine diabase from the north shore of Lake 
Onega, in the Caucasus. The olivine substance is entirely changed 
into aggregates and crystals of a non-pleochroic hornblende. 
vathrein® communicates an interesting paper on the altera- 
fion of garnet in the amphibolites of the Tyrolese Central 
Alps. Pseudomorphs of epidote, scapolite, oligoclase, horn- 
blende, saussurite and chlorite are described in detail. The scap- 
olite substance is intimately mixed with epidote and plagioclase, 
and the whole is surrounded by a rim of hornblende crystals. In 
the change to hornblende, crystals of magnetite separate and the 
excess of silica, magnesia and lime unite to form epidote. 
MiscELLANEous.—lIn a discussion concerning the conduct of the 
zeolites with reference to their water constituent, C. Bodewig* shows 
that the loss of weight which phacolite suffers over CaCl, must be 
due to loss of water of crystallization and not to loss of hygro- 
scopic water. He also contests the idea of Jannasch® that every 
desiccating agent abstracts a certain definite amount of water from 
ese minerals and consequently some of the loss over CaCl, may 
be due to loss of water of combination. The twelfth edition 
1 Ueber Kelyphite. Neues Jahrb, f. Miner., etc., 1884, J, p. 21. 
at Band 11, p. 73, 1885. 
Neues ae f. Mineralogie, 1885, 11, p. 78. 
E 
Ibp. 
5 Ib., p. go. 
` Zeitschrift f. Krystallographie, X, p. 433. 
: Miner. und Petrog. Mittheilungen, VII, p. 250. 
$ Zeitschrift für Krystallographie, x, p. 276. 
Ib., VII, p. 429. ' 
