800 The American Naturalist. [September, 
accompaniment of the melilite. The basanites have an andesitic habit 
and since they contain more or less sanidine, they approach phonolite 
in composition. Hornblendes, two monoclinic augites and nepheline 
are common as phenocrysts, while sanidine, plagioclase and olivine are 
scarce. The rock of Pilot Knob, near Austin, is a porphyritic neph- 
eline basalt. 
Eleolite Syenite from Eastern Ontario.—Adams, while 
making a geological reconnaissance in the township of Dungannon, 
Ontario, discovered a large area of eleolite syenite in the Laurentian 
of the region. The rock is notable especially for the fresh scapolite 
and calcite present in it and for the fact that its feldspathic constituent 
is an albite. Petrographically the syenite is an aggregate of the min- 
erals above mentioned and hornblende, biotite, sodalite, garnet and 
zircon. The nepheline is fresh. It occurs in large quantity, and 
sometimes in individuals two and a half feet in length. Its composi- 
tion according to Harrington is 
SiO, ALU, Fe,O, s MgO K,O Na,O Loss Total 
43.51 33.78 15 tr 540 1694 .40— 100.34 
The mica is a dark yellow-brown variety. It is present in small 
quantities only. Hornblende is also comparatively rare. It occurs in 
two varieties in different specimens. One variety has a large optical 
angle and a pleochroism of deep green and pale yellow tints. The 
other is allied to arfvedsonite. It has a small axial angle, and is pleo- 
chroic in deep bluish-green and yellowish-green tints. The scapolite 
is inlarge colorless grains that are fresh and seem to be original, and 
the calcite in more or less rounded individuals, often included within 
the other constituents. The feldspar is largely albite. A small quan- 
itity orothoclase occurs, especially associated with the sodalite. This 
orothoclase is thought to be secondary.’ An analysis of the sodalite 
gave: 
SiO, ALO, FeO NaO KO Cl SO, xx Ins. — Total 
36.58 31.05 .20 2481 .79 688 19 2 80 = 101.50 
O= Cl 1.55 — 99.95. 
Petrographical News.—The basic dyke material at Hamburg, 
Sussex Co., N. J., which was thought to be leucite tephrite by Hus- 
*Amer. Jour. Sci., 1894, XLVIII, p. 10. 
*Cf. also Geol. Surv. of Can., Vol. VI, Pt. J 
A rianan td onis r pd i 
