Review of Recent Geological Literature. 
335 
might be called “ metamorphic ” but it would be very doubtful pro¬ 
priety at best, and it would be far better to avoid the word in that con¬ 
nection, as being too thoroughly “ polarized ” and tending through its 
connotations to give an erroneous view of the origin of that rock. The 
same is true to an even greater extent with regard to the radiolarian 
cherts. 
Prof. J. P. Smith in a recent paper* describes “The Metamorphic 
series of Shasta county.” A brief inspection of his columnar section 
shows that he includes under that head over 6,000 feet of shales, soft 
limestones, shaly limestone, siliceous limestone, calcareous slates, 
argillites and tuffs, conglomerates, massive limestones and marbles. 
With the exception of the single mention of the word “ marbles” there 
is nothing in the entire series that would lead a petrographer to charac¬ 
terize it as metamorphic. 
In a paper just published! on the “Geology of eastern California,” 
Mr. Fairbanks groups together rocks ranging from the Cambrian to 
the Triassic inclusive as a “Metamorphic series.” Walcott has shown 
that in the White mountains (of this region) the Lower Cambrian is 
made up of arenaceous limestones, shaly limestones, siliceous slates 
and quartzites, with an aggregate thickness of 5,000 feet. It is proba¬ 
bly true that the later rocks are no more altered generally than these 
ancient beds, except where intruded by granite. The advisability of 
massing them all in a “metamorphic series” certainly calls for recon¬ 
sideration. 
Other examples might readily be given, but these will suffice to show 
how unaltered rocks of many different ages have not only been referred 
to as metamorphic , but, worst of all, generally called “the Metamorphic 
series.” When the term metamorphic is restricted to its proper use in 
Pacific Coast geology our views will become far clearer upon questions 
which have their own intrinsic difficulties, and are already sufficiently 
perplexing, without the additional obscurity that comes from inexact 
descriptions. F. L. Ransome. 
A Summary of Progress in Petrography in 1895. By W. S. Bayley. 
(From monthly notes in the Am. Naturalist. Waterville, Me., 1896. 
Price 50 cents.) We are pleased to note the appearance of No. 14 of 
these useful summaries, which are too well known to require extended 
notice. An index of subjects, and also one of authors, has been added, 
thus increasing the convenience of reference. u. s. G. 
^Journal of Geology, vol. n., p. 588. 
|Am. Geologist, Feb., 1896. 
