946 The Amerwcan Naturalist. (November, 
MINERALOGY AND PETROGRAPHY:' 
The Geology of the Kaiserstuhlgebirge, by Graeff,’ contains 
a resumé of the facts known concerning the structure of this celebrated 
region, and a brief synopsis of the characteristics of the interesting 
volcanic rocks occurring there. The tephrites, basanites, phonolites, 
limburgites, nephelinites and leucites found in dykes and flows in the 
mountains are described only briefly, as they are all well-known to 
petrographers. The loess, tufas and the crystallized limestone, the latter 
of which forms the central portion of the heights, are treated as briefly, 
except that in relation to the origin of the limestone the author enters 
upon a diseussion to show that it is probably a metamorphosed Jurassic 
rock. The most interesting portion of the paper is that which 
describes the inclusions in the eruptives. These are gneiss, granite, 
eleolite-syenite, and fragments of the voleanic rocks. They have all 
been more or less altered by the eruptive in which they are imbedded. 
The wollastonite and melanite crystals, both very common in the pho- 
nolite, are thought to be the remnants of metamorphosed limestone 
fragments. The most striking inclusions are those found in a phono- 
lite dyke near Obenbergen. They are often coarsely granular, and 
sometimes have rounded outlines. Their mineral constituents are the 
same as those of the including phonolite; but usually some one or 
more of them is completely lacking. Orthoclase, hauyne and nephe- 
line are the most abundant components, and hauyne the most persist- 
ent, entire inclusions sometimes consisting almost wholly of large 
idiomorphic hauyne crystals. Graeff supposes them to be the cooled 
intratellurial portions of the magma,. which on the surface yielded 
phonolite, that, after solidification, were brought to the surface by a sec- 
ond eruption of the same material. He believes the olivine bombs in 
basalts have an analogous origin, and that they are not simply concre- 
tions of the basic minerals of this rock. 
A Cyanite-Garnet-Granulite from the Tirolese Alps.— 
This rock, obtained some time ago by Cathrein, has been examined 
microscopically by Ploner.* The garnet and cyanite are both in large 
Edited by Dr. W. S. Bayley, Colby University, Waterville, Me. 
?Mitth, der Gross Badischen Geol., l.andesanst 2, xiv, p. 405. 
3Min. u. Petrog., Mitth. xii, p. 313. i 
