434 
The American Naturalist. [May, 
efforts made by that company to diminish the influence of the 
Banyans or East Indian merchants, who are the most honest 
and enterprising traders of these parts. The English company 
will take care to avoid this mistake. The number of East 
Banyans proper antedate the Portuguese in these parts. 
H. Trognotz giA 
.es the following as th 
e correct a 
reas of the 
countries of Sou 
th America ac 
cording to 
the latest data : 
Brazil - 
8.361,350 
Peru 
1,137,000 
Dutch Guiana 
78,900 
Bolivia 
1,334,200 
French Guiana 
129,100 
Chili 
776,000 
British Guiana 
- 229,600 
Argentine 
, Republic 
2,789,400 
Venezuela - 
1,043,900 
Uruguay 
- 
178,700 
Columbia - 
1,203,100 
Paraguay 
253,100 
Ecuador 
299,600 
17,813,950 
This is exlcus 
ive 
of the Falkland and Galapagos 
Islands. 
GEOLOGY AND PALEONTOLOGY. 
Prestwich on Underground Temperatures.' — The 
author treats the subject solely from the geological point of 
view. He gives tables of temperatures of coal mines, of min- 
eral mines, of artesian wells, and bore-holes, and of tunnels. 
After rejecting all doubtful and uncertain cases he obtains the 
following values for their several gradients: 
per I ° Fahr. 
Coal mines - - - 49.5 feet. 
Mineral mines - - - 43.2 " 
Artesian wells _ . _ 50.0 " 
The mean of the three thus gives a general thermometric 
gradient of 47.5 feet per degree. In view, however, of the 
many causes which have interfered with the value of even the 
best observations, the author thinks it may be a question 
whether a general average gradient of 45 feet per degree would 
not be nearer the true normal. 
» On Underground Temperatures, with Observations on the Conductivity of 
