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ÅA N:o 1) Igneous Rocks of Sviatoy Noss in Transbaikalia. 87 
H. S. Washington has repeatedly pointed out this remarkable 
example of the fact that chemically similar magmas may 
give rise to quite different sets of minerals. When discussing 
the genesis of these lime- and alkali-rich magmas the volca- 
nic leucite-bearing rocks may very well be taken as examples. 
The norm of the leucite-tephrite quoted — and more examples 
could be given — shows no wollastonite, and therefore one 
could expect that this rock, if consolidated under abyssal 
conditions, would contain diopside but no andradite. This 
would certainly be the case, if most of the potash content 
could crystallize as leucite. This mineral, however, does not 
seem to be constant under the conditions in which large batho- 
litic masses consolidate and in its place there is formed 
biotite which takes a part of the (Fe, Mg)O thus giving rise to 
excess femic lime. Consequently calcium-ferri-garnet could 
very well crystallize out from such a magma. In borolanites 
and malignites we have actual examples of the association 
of biotite and andradite: 
As noted above, there are varieties among the Canadian 
 nephelite-syenites and syenites containing andradite 2). There 
may be, among such varieties, some which are in composition 
very similar to the Sviatoy Noss rocks, but none of them has 
been analyzed hitherto. Detailed petrographic studies of 
them will be of much interest for the broblena of the genesis 
of alkaline magmas. 
No other examples of ndra esbenrine alkalifeldspar 
rocks are known to the writer. As to the occurrence of 
lime-ferri-garnet in igneous rocks in general, I shall leave the 
alkaline rocks containing titanium-bearing garnet, such as 
ijolite, alnöite and a few others, out of consideration, noting 
that such rocks must at any rate be genetically related to 
the sviatonossites, borolanites and malignites. In other rocks 
andradite is of rare occurrence. One of the few examples 
known is the k e d abe kite from Yelisavetpol in Caucasia, 
described by E. S. Fedoroff?). This andradite-bearing 
MRS D. Adams and A. E. Barlow, op. cit. 
>) E. C. ÖMeozopusr, »HKenmaBekyuTe vu Bionaute>, VaBtcria Mockos- 
ckaro CenbekOxosalicrBeHHaro MnctATyTa, VII, p. 43 (4901). 
