IV. GEOGRAPHY, GEOLOGY, ETC.--Petroleum and Coal in Venezuela.

Geographical Society of the Pacific.

The Behring's Straits Currents.--Proofs of their existence.

Experimental Geology.--Artificial production of calcareous pisolites

and oolites.--On crystals of anhydrous lime.--4 figures.

V. NATURAL HISTORY, ETC.--Coccidæ. By Dr. H. BEHR.--An important paper

read before the California Academy of Sciences.--The marvelous

fecundity of scale bugs.--Their uses.--Their ravages.--Methods of

destroying them.

Agricultural Items.

Timber Trees.

Blood Rains.

Scientific American Supplement, No. 286, June 25, 1881 · 第 6 / 71 题