40 
been found as accessory constituents: albite, anorthoclase, 
microcline, nosean, sodalite, apatite, sphene, zircon, 
garnet, fluorite, astrophyllite, mosandrite (?), ainigmatite (?) 
allanite (?). Of these accessory constituents, nosean, 
sphene and garnet are very common. An analysis of this 
rock from the Corporation quarry is given on p. 4I 
under No. I. 
Orthoclase presents the usual characteristics of the 
species, and is frequently somewhat turbid from the 
presence of minute inclusions. It occurs in individuals 
elongated parallel to the clinopinacoid and is intimately 
associated and at times intergrown with the other feldspars 
which occur as accessory constituents. 
Nepheline is so abundant that the rock gelatinizes 
readily when powdered and heated with dilute hydro- 
chloric acid. It often occurs in individuals as much as 
2 mm. in diameter. It is sometimes quite fresh, but is 
in places altered to cancrinite, hydronephelite, analcite 
and natrolite. These minerals also occur in little cavities 
and veins in the rock. Analyses of them by Dr. Harrington 
are given under V and VI, page 41. An analysis of the 
fresh nepheline separated from the nepheline syenite of the 
Corporation quarry was also made by Dr. Harrington and 
is given in the same table, No. II. 
The hornblende often possesses fairly good crystalline 
form. It is brown in colour and strongly pleochroic. 
The single individuals sometimes vary in composition, as 
shown by the varying depth in colour, and they very fre- 
quently have a greenish border. 
The pyroxene is in part a variety having a purplish 
colour and probably allied to that occurring in the essexite. 
But in addition to this variety of pyroxene, both aegerine 
and acmite occur in the rock and are sometimes present 
in the same slide. An analysis of the aegerine from one 
of the pegmatite veins of the nepheline syenite is given on 
p. 41, under No. IV. 
The mica is pale brown in colour and is present in 
distinctly subordinate amount. Lepidomelane, found in 
the pegmatitic segregations of the nepheline syenite, has 
been analysed by Dr. Harrington. 
Nosean which is not usually found as a constituent 
of nepheline syenite, is quite abundant in the rock, occur- 
ring as rather large, well defined idiomorphic crystals. 
It is usually turbid from the presence of minute inclusions 
and frequently shows a marked zonal structure. 
