Review of Recent Geological Literature. 
331 
found in the lowest currents ; but the grand cone is mostly composed 
of the second, which varies in structure from holocrystalline to vitreous, 
while the little summits consist of the third kind of ejecta. 
In the various facts given the authors see a record of the original 
great energy and gradual decay of the volcanic action which has now 
almost ceased, nothing but smoke and vapor issuing from the cone. 
Appended are a map and section of the volcano and several views of 
special points. e. w. c. 
Notes on the Areal Geology of Glacier hay , Alaska. H. P. Cushing. 
(Trans., N. Y. Acad, of Sciences, vol. xv, pp. 21-34, with map, Oct. 28, 
1895.) Argillite rocks are found to occupy large areas about the eastern 
side of the Muir inlet and glacier. On Mt. Wright they have an exposed 
section more than 3,000 feet thick. The mountains adjoining the larger 
part of Glacier bay, however, consist of dark dolomitic limestone, which 
overlies the argillites, apparently conformably, and attains a thickness 
of several thousand feet. This is named the Glacier Bay limestone, and 
from its scanty fossils is regarded as probably of Carboniferous age. 
The strata have undergone much regional metamorphism, being tilted, 
folded, faulted, and fractured. Diorites, including one type containing 
quartz and another free from it, are present, and may be of later date 
than the Carboniferous sediments. Dikes, chiefly of diabase, cut all 
the foregoing rocks, and are younger than the time of their disturbance 
and metamorphism. These dike rocks much resemble others of known 
Tertiary age which occur farther south. w. u. 
The Neocene Stratigraphy of the Santa Cruz Mountains of Califor¬ 
nia. By Geo. H. Ashley. (Proc. Calif. Acad. Sci., ser. 2, vol. 5, pp. 
273-367, pis. 22-25, 1895.) The first criticism occurring to the reader of 
this paper is that the author has sacrificed much of accurate observation 
and clearness of presentation to the somewhat natural zeal for covering 
a large area of interesting country,—a larger area than could very well 
be studied in the time at his disposal. The result has been to re-intro¬ 
duce into recorded California geology a certain amount of confusion, 
which, it had been hoped, was in a fair way to vanish, and incidentally, 
to call for an impartial criticism at the present time, in order that 
silence may not be construed as general acquiescence. 
The introduction of the new term “ Pescadero series ” for the assem¬ 
blage of rocks enumerated under that head, must be regarded as of 
very doubtful utility, embracing, as it is made to do by the writer, rocks 
thatcan be shown to belong to sharply different series, separated by 
conspicuous unconformities. In a previous paper on the Geology of the 
Coast Ranges* Prof. Lawson divides the rocks of the San Francisco 
peninsula into seven terranes, which comprise, in the order of their geo¬ 
logical age : 
1. Crystalline limestone. 
2. Granite, intrusive in the crystalline limestone. 
3. The Franciscan series. 
*Am. Geologist, vol. xv, pp. 342-356. 
