Some Canadian Rocks containing Scapolite. 187 
carefully examined the rock, refers the mineral to the spe- 
cies dipyr, calling the rock a dipyr diorite. 
It is believed by those who have studied the rock and its 
relations in the field, to be derived from the alteration of 
the true gabbro adjoining it, the pyroxene of the gabbro 
being altered to hornblende and the plagioclase of the gab- 
bro to scapolite.. The change would be essentially one of 
diagenesis. Intermediate varieties are found containing 
diallage “rests” in the hornblende and plagioclase mixed 
with scapolite.’ In this connection, an observation made 
by Fouqué and Michel Lévy’ is especially interesting, 
namely, that when the rock is fused and allowed to cool, 
the magma recrystallizes as a mixture of labradorite and 
angite. 
The occurrence of scapolite in certain of the crystalline 
schists, especially augite gneiss and amphibolite, has been 
mentioned by Tornebohm’, Dathe’, Becke’, Wulf,° Migge,’ 
Svedmark,° and others. The last-named author, in addition 
to a number of scapolite-bearing gneisses and amphibolites, 
describes an amphibolite from Orebro which contains s¢a- 
polite to the exclusion of plagioclase, and which also holds 
a little diallage and mica. In composition, therefore, it 
would be closely allied to the Oedegarden rock. 
Lacroix and Baret' have also recently described a pyrox- 
ene wernerite rock which occurs associated with gneiss 
' See Sjogren, loc. cit., and Rosenbusch, Mass. Gest. I., 165. 
*Sur la transformation par voie ignée, etc. Bull. Soc. Min. 
France. 1879. 105. 
* Ett par Skapolitforande Bergarter. Geol. Foren. i. St6ck. Forh. 
1882. VL 192. 
‘ Jahr. preuss. geol. Landesanstalt. 1884. LXXVI. 
* Die Gneissformation des niederésterr. Waldviertels. T. M. P. M. 
1882. 369. 
° Beitrag zur Petrographic des Hererolandes in Stidwest-Africa, 
T.M. P.M. 1887. 213. 
* Ueber einige Gesteine des Massai-Landes. N. J. Beil. Band. 
IV. Heft ITI. 
“Om nagra Svenska Skapolitfo6rande bergarter. Geol. Foren. i. 
Stock. Férh. VII. 1884, 293. 
