134 REGINALD A. DALY 
magma eruptible since the end of pre-Cambrian time. Foye has 
made an extraordinarily important contribution in showing the 
vast quantity of alkaline solutions which may emanate from granite 
invading a limestone terrane. Like Allan-he has given new, good 
evidence of the influence of gravity in the separation of magmatic 
phases. Foye corroborates the decision of Adams and Barlow as 
to the syntexis of limestone and granite in a complex now famous 
for its nephelite syenites. Quensel’s discovery of an analogy to 
Alno in the Almunge district and of the peculiar abundance of 
vesuvianite in the Almunge canadite is likewise to be particularly 
- recorded. The arguments presented by Cross, Marshall, Richards, 
and others against the sediment-syntectic explanation of the alkaline 
rocks are seen to be inconclusive. 
Shand finds the syntexis of limestone a partial explanation of 
undersaturation in igneous rocks. Smyth’s view concerning the 
alkaline series is not acceptable, on the ground that he fails to show 
cause for the local and exceptional assembling of alkaline elements 
from subalkaline magmas, assumed by him to be purely juvenile. 
Experiments by Ross and other students of the commercial-potash 
problem show the power of lime to volatilize the alkalies from 
feldspathic or clay mixtures, even at comparatively low tem- 
perature. 
Certain aspects of Bowen’s comprehensive theory have been 
studied. Serious doubt adheres to some of his fundamental postu- 
lates, summoned to explain the descent of alkali-rich rocks from 
subalkaline magma. On the other hand, many features of his 
excellent paper must receive hearty commendation from all thinking 
petrologists; in masterly fashion he has indicated many new, im- 
portant lines of thought and research. 
