122 The American Geologist. August, isga 
total population of this small state was 1,159,341, and the births exceed 
the deaths by 7,257, showing the native civilization to be on the in- 
crease. The catalogue of settlements is quite extensive, and shows the 
existence of one capital (Guadalajara), 17 cities, 30 villages, 188 pueblos, 
70 congregations, 387 haciendas, and 3,847 ranches 
The chapters relating to geography, geology and botany are of chief 
interest however. The grand volcano of Coluna is desci-ibed together 
with the other majestic peaks of this region. The valleys, canons and 
barancas, the basin plains, and every topographic feature are set forth 
clearly. 
The tables of altitude are so comprehensive that a contour map could 
be easily constructed from the data given. 
The third part, relating to geology, is of special interest. An excel- 
lent map is published. The oldest sedimentary rocks found are Cre- 
taceous, while eruptive and other igneous rocks predominate. The Ter- 
tiary history of the basins is of chief interest, showing as they do that 
most of the so-called Plateau region of Mexico is but the southern de- 
velopment of our own great basin region, with all of its wonderful his- 
tory of climatic changes and lacui^tral deposition. 
Part VI is devoted to the flora, especially its relation to altitude. A 
lengthy table gives the scientific and popular names of all the plants, 
their economic uses, and the geological formations which they inhabit. 
This part alone is one of the most intelligiljle contributions to plant 
distribution ever published on this continent. 
On the Clinton Iron Ore. C. H. Smyth, Jk. (Am. .Tour. Sci., xliii, 
1892, pp. 487-496) Perhaps more illustrative facts, and more arguments 
to show the derivative origin of certain hematites from a change of lime- 
stone, have been drawn from the Clinton ore than from those of any 
other horizon. There seems to have been a widespread acceptance of 
that theory, at least for those ores, and the theory has been applied, per- 
haps without due circumspection to other formations. Pseudomorphous 
replacement of some carbonate, generally a limestone, but sometimes an 
iron carbonate, has been applied widely to explain the iron ores of the 
lake Superior region. More lately original oceanic deposition from 
chemical solution has been put forward for some of the lake Superior 
ores, on the ground that there is not sufHcient evidence of the substitu- 
tion theory. Now Mr. Smyth proposes to remove from the substitution 
hypothesis its original cause and key, and to place the Clinton hema- 
tites in the category of original chemical deposits of date coeval with 
the enclosing strata. 
This result he bases on a careful and lengthy study of this ore at the 
typical locality, Clinton, N. Y., and in detail the steps of the proof are 
somewhat as follows: 
1. The ore is not embraced in limestone, but in shales and sandstones, 
the latter so coarse sometimes as to be conglomerate. 
2. The beds are nearly or quite horizontal, and not so placed as to 
allow easy and rapid access of ferriferous waters. 
