70 Pentti Eskola. (LXIII 
Scapolite has rarely been noted as an original consti- 
tuent of igneous rocks. Rosenbusch and Iddings in their 
text-books deny the existence of primary pyrogeneous : 
scapolite. 
Lately, however, many examples have been recorded of 
scapolite as primary crystallization in igneous rocks. From 
granite-pegmatites it has been described by J. Stansfield 7), 
J. Schetelig ?) and A. Laitakari 2). I myself have observed 
it frequently in the pegmatites of southern Finland. 
But the scapolite also occurs in true deep-seated igneous 
rocks other than pegmatite. In their description of the min- 
erals in the nephelite-syenites of the Haliburton and Ban- 
croft areas, Adams and Barlow give an account of the scapo- 
lite 2): »This mineral is a frequent and often abundant 
constituent of the nepheline-syenite, occurring in clear colour- 
less grains, which meet the äccompanying nepheline and 
feldspar grains with a perfectly sharp outline, and no hint 
of alteration or weathering.» The occurrence of the scapolite 
in the pyroxene-hornblende-syenite on Sviatoy Noss seems 
to be very like that described by Adams and Barlow and 
the scapolite is here certainly of primary origin, in so far as 
it has crystallized out from the magma in the same way as 
the other constituents. 
That the scapolite might crystallize out from magma is | 
only what may be expected considering the fact that the 
temperature and pressure conditions and the content of 
mineralizers in a crystallizing magma must often be identical 
with those prevailing under metamorphism, either normal 
or pneumatolytic. 
Aplitic epidote-syenite. Thus may be called a 
white rock of finely granular sugar-like appearance cropping 
out at point 74 A and 75 A. There are quartz-bearing gra- 
nitic varieties, but some specimens were found to contain 
1) Am. J. Sc. 1914, 3, 7. 
?) Norsk Geologisk Tidskrift, III, 1915. 
3) Bull. Comm. géol. Finl. N:o 46, 1916. 
?) Frank D. Adams and Alfred E. Barlow, op. cit. p. 242 (1910). 
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