56 University Geological Survey of Kansas. 
England in the Cambro-Silurian. The deposits of Andreas- 
burg in Germany, of Pontpean in France, and of Horcajo in 
Spain are in Silurian rocks, and some of those of Tomsk, 
Siberia. The more important bodies of Sardinia and of 
Linares, Spain, are principally in the Cambrian and $i- 
lurian. The deposits of Laurium, Greece, are also probably 
in Silurian rocks. In South America lodes of Bolivia are in © 
Silurian rocks. 
‘* Deposits in Devonian Rocks.—In America, only a few im- 
portant lead and zine deposits are assigned to this horizon. 
The most important are a portion of the ore bodies of Eureka, 
Nevada, and the silver-lead bearing lodes of Guanajuato and 
others of central Mexico. In Europe such are comparatively 
common. Among these are included deposits described in 
Cornwall and Devonshire, England; in the Siebengebirge, 
at Eifel, Gladbach, Iserlohn, Holzappel and the Hartz moun- 
tains, especially at Rammelsberg, allin Germany. The lodes 
of Huelgoat and Poullaouen, in Brittany, penetrate Devonian 
as well as other rocks, and some of the deposits of Tomsk, 
Siberia, also belong to this formation. 
‘Deposits in Carboniferous Rocks.—Almost all lead and zinc 
ores of the Carboniferous are in the Lower Carboniferous 
series, which are generally limestones. ‘To these belong the 
lead deposits of Leadville and Aspen, Colo., and others of 
Utah. The zinc and lead ores of southwestern Missouri are 
also in these rocks. In Europe are the deposits of Derby- 
shire and the north of England counties, and those of Flint- 
shire and Denbighshire; those of Bleiberg and Vieille 
Montagne in Belgium; in part those of Huelgoat and 
Poullaouen in France; those of Santander in Spain, and 
of Tomsk in Siberia, both also in part. At Carthagena in 
Spain are deposits in the Permian. 
‘Deposits in Triassic Rocks.—No great lead or zinc deposits 
in Triassic rocks have developed in America, though some of 
the lodes of central Mexico, carrying silver-lead ores, are in 
these rocks. In Europe, on the contrary, this horizon is a 
great source of supply. Prominent among the Triassic ores, 
we may cite those of Carinthia in Austria, those of Upper 
Silesia in Prussia, of Mechernich in the Rhine provinces, 
