120 Scientific Intelligence. a 
In the department of geology proper, our explorations have extended — 
over portions of forty of the forty-six counties into which the State is 
divided; and when it is remembered that the average size of a count 
is equal to half that of the State of Massachusets, (California having 
jus: twenty-four times the area of that cee some idea of the m 
tude of our work may be obtained. The chain of the Sierra Nevada 
may be parallelized with that of the Alps for extent and average elevae 
tion; while the ree — are nearly as extensive as the Appalachian ‘ 
chain of mountai 2 
Coast Ranges fro Angeles to Clear Lake; the vicinity of 
of San Francisco aes cae worked out in considerable — ine 
all of San Francisco, San Mateo, Santa Clara, Alameda, : 
dati ur observations have also been extended to the Washoe — 
Region, e have received considerable collections “ nee from the 
Humboldt Miviog District, (known by this name on Pacific Coast, - 
but designated on Warren’s Map as the “ West ale yee River Range,” 
and in longitude 118°,) by which we have been able to fix the age ies 
formations in that region 
r. Gabb has been chiefly occupied, the past year, in iene ng and 
seribing the Cretaceous fossils of the Coast Ranges and t foun na 
the Sierra, of which he has nearly two hundred new s ot re: 
publication. He has also described the Triassic fossils, collected by ie 
Survey at Washoe, and by Gorham Blake, Esq., in the Humboldt Range 
The fossils older than the Trias have been referred to Mr. Meek for inve® 
tigation. A portion of the fossil plants have been placed in the hands of 
Dr. J. S. Newberry for description. , 
_ It is to the department of General Geology that, up to the present 
it contains, is then to be laid down upon the map, in ‘the 
in which its outerop dni on te surface. The general ch 
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