1876.) Geography and Exploration. 501 
In a physical point of view, the isthmus may be considered as divided 
into three parts : first, an eastern, extending from the Gulf of Mexico to 
the Puerta ; secondly, a central, from the Puerta to the Chivela ; and 
thirdly, a western, from the Chivela to the Pacific. The eastern part, 
formed principally of alluvial land and watered by the Coatzacoalcos and 
its afluents, has its largest portion covered with thick and damp forests, 
whose vegetation rivals the greatest beauties of tropical nature. The 
central region presents an undulating surface, embossed with innumera- 
ble lomas, or hills, which, rising gradually, unite on the western side with 
the mountains of the Sierra de los Mijes, and toward the east with those. 
of the Sierra de Chimalapa. Although watered by numerous streams, it 
presents, nevertheless, but a scanty vegetation, essentially characterized - 
byoaks on the side of Sarabbia, and palm-trees on the plateau of Chivela. 
The western division, or plains of the Pacific, is very dry, and its vegeta- 
ble physiognomy presents a striking contrast to the rich plains on the 
_ Atlantic slope. Of the few rivers which flow through it, the most im- 
portant are the Tehuantepec, Juchitan, Chicapa, and Ostula. These 
are so low during part of the dry season that the inhabitants of the vil- 
lages and ranchos situated on their banks have no drinking-water but 
that which they drawout of holes dug in the sand. 
Resources or toe Brack Hits. —In Mr. Jenney’s Mineral 
Wealth, Climate, etc., of the Black Hills of Dakota, we have an appar- 
ently authentic aétount of the natural resources of this region. Com- 
pared with some of the world-renowned districts in California and Aus- 
tralia, the placers at present discovered are not remarkably rich, yet there 
are claims already opened and worked which are yielding a very good 
return for the labor employed. The reporter adds that the climate of 
the Black Hills is wonderfully healthy and invigorating, and that wood, 
a and grass are everywhere abundant and of the best quality. 
There is gold enough to thoroughly settle and develop the country, 
and, after the placers are exhausted, stock-raising will be the great busi- 
hess of the inhabitants, who have a world of wealth in the splendid 
stazing of this region.” i 
SIBERIAN ExPLoRraTIon. — Drs. Finsch and Brehm and Count Wald- 
Zeil arrived at Ekaterinburg, April 5th, on their way to Siberia. 
Dr. Nordenskiöld’s plan for following up his voyage of last summer from 
ay to Siberia, is to start from Gothenburg July 7th, in a steamer 
capable of taking 10,000 puds weight of cargo. He will go up the 
