W. M. Davis—Origin of Drumlins. » 411 
but the detailed study that it would well repay has not yet 
been attempted. Members of this series occur near Charlton 
-station, Boston and Albany railroad, with their bases at an 
elevation of 900 feet above sea-level, and others stand still 
igher. The portion of the group in Connecticut is described 
by Percival as follows. ‘The district extending north from 
Hampton, through Abington, Pomfret and Woodstock, is char- 
‘ acterized by a series of very smoothly rounded, detached hills, — 
in which the rock is usually entirely concealed. ese form a 
striking contrast with the longer and more continuous [rocky] 
ridges of the adjoining formations” (Geol. Conn., 1842, 256: 
also 461, 479, 485). Prof. G. H. Stone reports that drumlins 
-of large size, like those about Boston, have not been found in 
Maine. Western New York, between Syracuse and Rochester 
presents a surprising number of parallel, north-and-south drift 
hills, probably familiar to many travelers by rail. Some 
of them are so long, smooth and even that the country there- 
abouts has been described as fluted. These were long ago 
described by Prof. Jas. Hall in his Geology of the 4th district 
of New York (1843); since then they have been strangely 
neglected until examined by Dr. L. Johnson, who has lately 
published a paper entitled “The parallel drift-hills of Western 
New York” (Trans. N. Y. Acad. Sci., 1882, i, 77). Some of 
the ridges are “two or three miles long, and attain elevations 
of 100 or 200 feet above the intervening valleys; but the 
greater number are shorter and steeper. Man of them were, 
length, with corresponding linear marshes interspersed, ese 
correspond accurately to the direction of ice motion.’ (Geol. 
t found in the abundant drift of Minnesota. A few 
examples are mentioned for Pennsylvania near its western 
border by Prof, Lewis. (2d Geol. Surv. Pa., Terminal Moraine, 
1884, 29, 188.) It is evident enough from this review that the 
distribution of drumlins is insufficiently known. : 
gin.—The earliest discussion of the origin of drumlins 
that I have found is in Sir James Hall’s interesting paper on 
“the Revolutions of the Earth’s Surface (Trans. Edinb. Roy. Soc., 
