SO-CALLED PORPHYRITIC GNEISS OF NEW HAMPSHIRE 789 
north of Wickwas pond. But there is nothing to indicate that 
any batholite as a whole has undergone any such enormous 
stresses as have affected the anorthosite of Canada, the proto- 
gine of the Alps, or even the gneisses of the Malvern hills.’ 
Under the microscope the New Hampshire rock always shows 
that the essential minerals crystallized in place and that they 
have only been affected, except locality, by moderate pressures. 
From the complete satisfaction of these several criteria one 
cannot escape the conviction that the foliation of the porphy- 
ritic granite has nothing to do with stratification, and has not 
been caused by the alignment of the constituents in a time of 
pressure metamorphism acting on a consolidated rock. 
The significance of the uniformity of the porphyritic granite and tts 
wide geological distribution One of the most striking character- 
istics of the porphyritic granite is the lithological sameness 
which pertains to it to a great degree throughout all the areas 
examined. This property is retained irrespectively of the nature 
of the rock-terranes which it invades. From the many examples 
of endomorphic changes induced in plutonic rocks by the melting 
up of foreign inclusions, we have selected a few which are 
described in the annexed footnote.” In view of this principle, 
tT CALLAWAY, Q. J. Geol. Soc., 1887, p. 525. 
2 Michael Lévy finds that by an endogenous action granulite cutting diabases and 
diorites is enriched in plagioclase at the contact (Bull. de la Soc. Géol. de France 
1882-3, p. 296). Lehmann states that where the granitite of Dobeln is intruded 
into biotite-bearing rock, it is practically unchanged, but when it cuts in contact with 
sericitic schists, siricite is an important constituent (Untersuch. tiber Ent. d. altkryst. 
Schiefergesteine, Bonn, 1884, p. 19). Again, on classic ground, Lawson determines 
his Rainy Lake eruptive rock to bea quartzose biotite-granite gneiss where it comes 
in contact with quartz porphyries, yet the same rock-body cutting the more basic horn- 
blende schists becomes a hornblende syenite with little quartz (Ann. Rep. Geol. Surv. 
Canada, 1887-8, F, 31). In one of the great batholites of western Massachusetts, Emer- 
son notes three phasal differentiations, a heavy hornblende granite, a hornblende gran- 
itite, and a granite proper, all of which he attributes to the melting up of three 
various sorts of crystalline schists respectively (Bull. Geol. Soc. Am., I, 1890, p. 559). 
A similar affection of a porphyritic granite by a hornblendic country-rock is found in 
Chor Mountain, India (Geology of India, 2d ed., by Oldham; Strat.and Struc., p. 43); 
while quite recently Harker notes a good case of a relatively basic modification of 
granophyre at its junction with gabbro, and ascribes it mainly to an incorporation of 
re-fused gabbro (Q. J. Geol. Soc., 1895, p. 134). 
