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Editorial Notes. 
Within recent years there has been no field of geology which has produced more 
abundant and fruitful results than that of glaciology. So many able workers have 
cultivated it that it has become difficult for any save the specialist to keep pace 
with the developments, and every teacher of geology has felt the great need of 
some work of moderate size, for his own information or for placing in the hands 
of his pupils for collateral reading. Such a work, by Prof. I. C. Russell,* has just 
appeared, and teachers of Geology, will heartily welcome it. In his ‘‘ Glaciers of 
North America” is given a sufficiently full discussion of the science of glaciers in 
general, their origin, flow, physical features, effects their bearings on climate, 
etc., together with a detailed description of the North American glaciers, big and 
little. The work is clear, it is interesting, it is most admirably illustrated and 
the author's reputation as a geologist is a sufficient guarantee of its accuracy, No 
continent offers better material for the study of glaciers than does our own, and 
now their science is put into an available shape for both teacher and student. 
S. W. W. 
During the past year there have appeared three most excellent works in general 
entomology. All are indispensable, supplying, as they do, the different needs of 
the student. The first and most pretentious of these is by Dr. D. Sharp in the 
‘Cambridge Natural History.’ Dr. Sharp's extraordinary acquaintance with the 
literature of insects, as editor of the Zoological Record, has given him the ability 
to produce a most excellent and readable work of general reference for the library. 
The ‘‘ Manual for the Study of Insects,”’ by Prof. ]. H. Comstock is a text book 
for use in colleges and universities where systematic and structural entomology 
are pursued, and in these fields it is unequalled. For the first time it permits the 
student to ascertain to which families the insects that he studies belong. The 
figures, by Mrs. Comstock, are nearly all new, a feature that is welcome, and, best 
of all, they are very accurate and clear. 
The third work, ‘‘Economic Entomology,” by Prof. J. B. Smith, while not as 
extensive as Prof. Comstock’s work, is one that is most heartily welcome. It has 
no rival in its own field, that of applied entomology and is also an excellent 
adjunct in systematic entomology. Prof, Smith's long experience in both economic 
and systematic entomology has well fitted him for the task be undertook, and he is 
to be congratulated upon the success with which he has accomplished it. S.W. W. 
*Glaciers of North America, A Reading lesson for students of Geography and Geolo- 
gy, Ginn & Co,, 1897, 
