y SN 
lan 
98 r é Pentti Eskola. | (LXT 
up of the Coutchiching series. Lawson discusses only differ- 
entiation as a factor in the genesis of the malignites. Smith, 
who has given a field record of the surrounding country, 
states the Coutchiching series to be characterized especially 
by the absence of limestone ?). The contacts are, however, still 
insufficiently known, so that this example cannot be used 
either for or against the assimilation theory. 
Very close genetical analogy to the sviatonossite is found 
in the kedabekite which, according to Fedoroff 23), has origina- 
ted from a diabase-porphyrite magma which has assimilated 
an augite-garnet-rock (= andradite-pyroxene-skarn) con- 
taining copper ores. 
The sviatonossite is a true igneous rock of the composition -: 
of syenite to which is added lime, containing alkali feldspars, 
aegirite-augite and andradite as ordinary constituents. It 
has originated by an assimilation process from the granite- 
magma of the neighbouring large batholith: this has first 
produced andradite-skarn and subsequently, at deeper 
levels, resorbed it again. Finally the constituents, have cry- 
stallized out in the regular way. This rock deserves quite a 
particular interest as presenting a concrete example of how 
alkaline rocks may be formed by the action of magma on 
limestone, in agreement with Daly's well-known theory. 
Moreover the phenomena observed in the skarn blocks scät- 
tered in the sviatonossite illustrate the theory of the origin 
of skarn by metasomatic action on limestone. 
The present paper is an abstract from the reports of the 
Moscowian Expedition in search of radium, sent in 1914 to 
Transbaikalia, for the most part at the expense of Mr. P. 
Ryaboushinsky in Moscow. The leader of the expedition 
was Mr. M. Soboleff, as mineralogist followed Dr. A. Himmel- 
bauer, and as geologists and petrographers Mr. K. Viscont 
and the present writer. — The expedition explored parts of 
the peninsula of Sviatoy Noss, the Bargousin Valley and 
!) Smith, Annual Report Geol. Survey of Canada, Vol. V, 1890—91, 
part G. Hunter Island Sheet. d 
?) E. S. Fedoroff, loc. cit. (M3B. Mock. Cexbekoxo3. MHcrt. VII, 1901). p. 43. 
