Hornblende-Basalt in Xorthern California. — Diller. 253 
few miles west of Freeport, where it rather abruptly changed 
to the northwest and continued so to the outer drift margin. 
2. The wier f/e r//''/ce, in retreating, withdrew more rapidly 
in the southern portion of the district than in the northern. 
The belt between the outer margin and No. 3, in which the 
deposits of stratified drift are very poorly developed, and 
which is twelve miles wide on a line due west of Freeport, 
may widen out toward the south so as to constitute perhaps 
the entire width of the exposed area of Kansan drift south of 
Rock river. The next great belt of Kansan drift, which con- 
tains heavy deposits of stratified drift of the esker series, and 
which is twenty miles wide in the Pecatonica basin, probably 
broadens out toward the southeast; but, passing under later 
drift sheets, it is perhaps not exposed south of the Rock 
river. 
3. The esker belts, with therr " areas of special develop- 
ment," and the angular gravel deposits, being demonstrably 
contemporaneous phenomena, postulate a very vigorous move- 
ment in the glacier at the same time that its borders were be- 
ing rapidly melted. 
In short, from a study of the phenomena displayed by the 
older drift in the Pecatonica basin, we learn that the ice-sheet 
of the Kansan epoch, at least in one district, and probably in 
all, was not of such insignificance and inefficiency as many 
glacialists have supposed. 
HORNBLENDE-BASALT IN NORTHERN 
CALIFORNIA. 
By .J. y. Diller, Washinf?ton, D. C. 
While making a geological survey of the Pitt river region, 
at its great bend, in Shasta county, California, I found in 
Kosk creek, about a mile above its mouth, a large, well-worn 
cobble-stone of an eruptive, quite unlike any other yet ob- 
served in that district. The locality is just beyond the north- 
west corner of the Lassen Peak sheet of the U. S. Geological 
Survey. Although not found in situ, this brief notice of the 
rock may be warranted on account of the rarity of its tjq^e in 
this country. The fragment was evidently brought down by 
the stream from the rugged canyon above, where a large series 
of Paleozoic, Mesozoic and Cenozoic sedimentary rocks are 
associated with various eruptions. 
