PENNSYLVANIA ANORTHOSITES 
31 
aggregate of basic plagioclase,” but no reference to anorthosites 
can be found in the recent reports of New Jersey. It is possible 
that Lawson had reference to certain feldspathic facies of the 
quartz diorite or gabbro of the Highland region which are known, 
respectively, as the Losee and Pochuck gneisses.® E. C. E. Lord ® 
describes “labradorfels” from Burnt Head, Monhegan Island, 
Maine, associated with norite and gabbro-pyroxenite. The anor¬ 
thosite and pyroxenite, which are extreme differentiates of a nori- 
tic magma, occur as “dike-like masses (segregation veins)” . . . 
having “an irregular lenticular form without persistency in strike 
or dip. They can rarely be followed for more than twenty to 
thirty yards, and terminate generally in narrow veins and string¬ 
ers while merging laterally into the surrounding rock without 
definite planes of contact.” Between these two extreme differ¬ 
entiates, “bands of extremely coarse-grained norite occupy miner- 
alogically and geologically an intermediate position.” ^ Evidently 
these feldspathic segregations, although numerous, do not occur 
in large masses. They may represent original banding in the 
norite comparable to the banding in the gabbro of the Isle of 
Skye,® as noted by Geikie and Teall, or in the Duluth gabbro,^ 
as mentioned by Grout. Brief mention is made by Pardee of a 
thoroughly crushed and sheared anorthosite associated with a 
strongly laminated granite in Shoshone County, Idaho. These 
rocks are considered very ancient pre-Cambrian intrusives. So 
far as known no other occurrences of anorthosite are reported 
from North America. 
In Norway, great masses of anorthosite, associated with gabbro 
intrusives, are described by Kolderup,^^, Vogt,^^ Kjerulf,^® and 
Helland; in Sweden anorthosite is described by Hogbom; in 
Volhynia, Kiev, Podolie, and Kherson districts of Southern Rus¬ 
sia by Ossowski,^® Schrauf,^^ Tarrasenko,^® von Crustschoff,^® 
5 Final Kept. Ser. State Geologist, N. J., Vol. VII, pp. 121 122, 1910. 
6 American Geologist, Vol. XXVI, pp. 329-347, 1900. 
7 American Geologist, Vol. XXVI, pp. 338-339, 1900. 
8 Quart. Journ. Geol. Soc., London, Vol. L, pp. 645-659, 1894. 
9 Journal Geology, Vol. XXVI, pp. 439-458, 1918. 
10 Bull. U. S. Geol. Surv. No. 470, pp. 45-46, 1911. 
11 Bergens Mus. Aarbog, No. 5, 1896, No. 7, 1898, No. 12, 1903. 
12 Videns. Selsk. Skr., Vol. I, No. 10, 1908. 
13 Die Geologie des sudl. und mittleren Norwegen, 1857. 
14 Helland, collaborated with Vogt. > 
15 Geol. Foren. Stockholm Forhand., Band XXXI, 1909. 
16 Comptes Rendus de I’Academie des Arts et Sciences de Krakavie, Mai, 1879. 
17 Sitzb. der k. Acad. Wiss., Wien, Band LX, abt. I, 1869. 
18 Abh. Nat. Gesell. Kiew, 1886. 
19 Tschermak’s Min. u. pet. Mitt., Bd. IX, pp. 470-527, 1888. 
