Scientific Intelligence. 237 
and fine. The ridges, which rise 2,000 to 6,000 above the level of 
the valleys, trend nearly north-and-south, are approximately par- 
allel, and vary from five to ten miles in width. ~— pesca sedi- 
mentary strata are also con wauisd to a large extent by great out- 
flows of Tertiary volcanic ae which have spr sh in all air ections 
from the old lines of uphe 
Between the Desert Region—an arm of the Salt Lake Valley 
lying to the west of the Aqui Mountains—and the first ridge 
called the Ibenpah Mountains, there are terraces at the heights 
800 feet, 500 feet and 300 feet, above the Desert level, the second 
marked by calcareous tufa. 
The Wachoe Mountains, rising out of the Gosi-Ute Desert, con- 
— with the north-and-south lines of Paleozoic ridges in consist- 
ing of a dark reddish-gray granite, dioryte and quartz-porphyry, 
and outside of these a Coal-measure limestone, and then weer a 
and rhyolytes. The granite contains little quartz, and affor 
Professor T. M. Drown only 55°53 per cent of silica, with 5°20 of 
potash, 4:84 of soda and 5°62 of lime. The so-c o-called “ andesyte” 
1s really, not a hornblende rock (hornblende grains being exceed- 
ingly rare), but contains much biotite, along with a triclinic feld- 
spar. One of the two agreeing analyses by Mr. pe odward ob- 
tained Silica 67°63, alumina 18°08, iron protoxide 2°17, magnesia 
1°14, lime 3-16, soda 2° 87, potassa bse 86, ignition 1 -49=100" 40, 
agrecing little with ordinary andesyt 
ast Humboldt Range is the in range of Central Nevada, 
and the highest between the Wahsatch of Utah and the Sierra 
Nevada. One of the peaks, Mt. —=? has a height of 11,321 
feet and several are over 10, _ feet. A mass of Archean rocks 
unconformably, Devonian and Carboniferous strata. There are 
numerous cafions in the limestone of the eastern slo All the 
ridges of the plateau are — in detail in the Report, and 
also _— of the N oye Bas 
eport makes an ex ale nt companion volume to that on 
the Petrology of the 40th puradiel by Zirkel, it explaining at length 
the geological ~~ of the rocks. Many chemical es of 
rocks are given, the most of them by ) ; W. Woodward. 
Besides the lags and heaatiflly-colored Atlas already pee 
in this Journal, there are many most excellent ambrotype plates 
in the text, which are sacaiiskokle for their topographic and 
a Australiensis: a Deseription of the Plants of the Aus- 
tralian Birnieorys By Groret Bentuam, F.R.S., assisted by 
Baron Ferdinand von Masler, F.R.S., ote: &e. Vol. VIL Row 
burghiacee to Filices. London: Reeve & Co. 1878. 806 pp., 8vo. 
—This volume brings a great lg a happy completion. 
volume was issued in the year 1863, and the work has 
— steady ea ise to the end. It is the complete phenoga- 
a continent, and the only one; is worked up by one 
