1256 Hie American Geologist. October, 1892 
produced to the close of 1891 exceeds ninety-three and a half millions. 
The. value of silver and silver ores produced in 1891, exceeds three and 
a half millions, a value greater than all the rest of the minerals together. 
Coal comes next in importance, its value for the year being about one 
and three-fourths millions. Tin was produced to the value of £271,412, 
while of iron the value amounted only to £36,101. Bituminous and 
Jcerosene shales have a value in the colony and are mined and utilized to 
the amount of more than 40,000 tons. Indeed some of the coals, if we 
may judge from the analyses, are little better than the product known 
as shales. Of the coal, however, which is all of Mesozoic age, more 
than 4,000,000 tons were raised during the year covered by the report. 
There are detailed reports on the several mines and mining districts. 
There are tables showing number of men employed in mining, and 
number of accidents that occurred during the year. Besides the sub- 
jects usually found in mining reports we find a Water Conservation Re- 
port, which refers to public watering places established on the main 
stock routes of the colony for the convenience of traveling stock. All 
the watering places, with a few exceptions, are under the direction of 
caretakers who collect fees for the privilege of watering animals at so 
much a head. Some of these places are leased; in the case of those not 
leased, the fees are forwarded to the treasury. There are also reports 
from the Superintendent of Caves, a public office unknown in America. 
In an article in the fifteenth volume of the Journal of tJie Cincinnati 
Society of Natural History, Mr. J. F. James continues his summary of 
the Paheontology of the Cincinnati Group, enumerating and reprinting 
descriptions of the species of Stromatopara, 8tromatocerium and Beat- 
ricea, also those of Columnaria among the Actinozoa. The paper will be 
continued. 
The same writer also discusses the preservation of plants as fossils, 
showing how the mere impression of a leaf or other organ may in some 
cases be preserved, though not a vestige of the actual substance may 
remain to be fossilized. 
Mr. Whitman Cross, in the American Journal of Science (July, 1892), 
describes a series of strata in Colorado which fill a part of the gap exist- 
ing between the top of the Laramie (Cretaceous) and the lowest recog- 
nized Eocene beds. "The facts of stratigraphy and lithology show that 
in Colorado the great conformable series of Cretaceous formations ended 
with the coal-bearing Laramie strata. Deposition plainly ceased in this 
region because continental elevation, which had long been in progress, 
finally caiised the retreat of the Laramie seas." "When sedimentation 
again began it was in comparatively small lakes or seas. In the pebbles 
of the Arapahoe beds is the record of the slow erosion of 14,000 feet of 
strata, from the Laramie down to the red beds of the Trias." 
Then followed volcanic outbursts over a large area, not however nec- 
essarily requiring a very long era for their occurrence. The thickness 
of the Middle Park beds, the lower half of which is ia great part vol- 
