130 PROCEEDINGS OF THE BOSTON MEETING 



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feet to nearly 3,500 feet higher, including McKenzie and Street Mountains, 

 Mount Whiteface, the Sentinel Range, and Mount Marcy, the last being the 

 highest peak of this great mountainous region. These summits were envel- 

 oped by the continental ice-sheet at its time of greatest thickness, and during 

 its final melting the drumlins were amassed and molded by glacial currents 

 beneath the weight of a relatively thin remnant of the waning ice-fields. 



Presented by title in the absence of the author. 



EXTREMES OF MOUNTAIN-GLACIER EROSION 

 BY WILLIAM HERBERT HOBBS 



(Abstract) 



A comparative study of different glaciated mountain districts as illustrating 

 stages of the erosion cycle of mountain glaciation. The Glacier National Park 

 appears to represent an extremely late stage. If the Big Horn Range and the 

 Alpine Highland be taken to represent respectively the grooved or channeled 

 upland and the fretted upland and correspond to the stages of youth and 

 maturity, the Glacier National Park may be described as a monumented up- 

 land, and to represent the old-age stage of the cycle. The relation in position 

 of the erosion residuals in such a monumented upland to the glacial cirques 

 is quite different from that of the horns in a district like the Alps. 



Presented by title in the absence of the author. 



DISPERSION OF STONES IN THE DRIFT, IN NEW HAMPSHIRE 

 BY JAMES WALTER GOLDTHWAIT 



(Abstract) 



A state-wide survey of road materials for the State Highway Department 

 in 1917 and 1919, in which attention was directed particularly to the study 

 of the distribution of various types of ground moraine and gravel, has 

 afforded opportunity to collect a mass of information regarding the paths 

 followed by fragments of native rock during the Pleistocene glaciation of 

 New Hampshire. The percentages of different types of rock have been counted 

 in samples of ground moraine and gravel from more than 250 localities ; and 

 these data, when plotted on the geological map of the State, show clearly 

 the relation of the drift stones to the parent areas and to the course of the 

 Wisconsin ice-sheet as recorded by striae. By this means one reaches the 

 conclusions that: (a) there is a strong prevalence of strictly local material 

 in the drift; (ft) great heterogeneity characterizes those gravels and tills 

 which were fed from a number of small and diverse rock areas, while sim- 

 plicity of composition characterizes those deposits which lie on or immediately 

 southeast of wide belts of rock; (c) there are great differences in the amount 

 of stony material and in the average size of the stones in the drift, according' 

 to the massive or fissile character of the parent rocks and the durability 

 of the fragments during transportation; (d) percentage counts of drift stones 



