58 Recent Literature. [January, 
If anything is wanting in the pages of the book before us, it is 
facts bearing on the psychology of these animals, such as are to 
be found in Morgan’s work on the beaver. Studies of this kind 
have, however, to be mostly carried on with animals kept in con- 
finement. 
Regarding the change of color in the winter and summer pel- 
age, Dr. Merriam has a good deal to say, as we have shown in a 
previous notice of the early part of this work, which originally 
appeared in the Transactions of the Linnæan Society of New 
York. Under the head of the varying hare the’ subject is again 
taken up, and the author insists that the change of color is due 
to the presence or absence of snow, or in his own words: “ Both 
in spring and fall the time of the change seems to be governed by 
the presence or absence of snow, and is not affected by the tem- 
perature.” A careful, detailed and comparative study of this sub- 
ject is much needed. So far as we have looked into the matter, 
we have been disposed to consider Dr. Merriam’s views with 
favor, but have learned from hunters facts which seem to show 
that temperature is not wholly without influence in producing 
the change. But why should not all of our northern mammals 
- which do not hibernate, but are abroad when the snow is on the 
ground change their pelage? Why are the varying hare, ermine, 
arctic fox, etc., the only animals which change? Why do not 
the fisher and mink change as well as the ermine ? 
Whether the lay reader will be pleased with the use of the tri- 
nomial nomenclature remains to be seen. Perhaps occasionally 
useful in a strictly scientific treatise, why should not Scinropterus 
volucella hudsonius, read Sciuropterus volucella var. hudsonius ; the 
uninitiated reader would then understand that a well recognized 
variety of the ordinary more southern flying squirrel was meant. 
It is to be hoped that our trinomialists will not “run the thing 
into the ground.” 
e find no occasion for criticism in this admirable book, and 
excerpt some paragraphs concerning topics which appear new and 
fresh, though for that matter the entire volume smacks of out-of- 
door life, is redolent of the spruce and pine woods, and carries us 
back to the clear skies and sylvan retreats and mountain lakes of 
the noble Adirondack forests, 
Speaking of the mole Dr. Merriam writes: 
“The modification of structure that adapts this animal to its 
cartilaginous snout, and unencumbered with external ears or eyes 
to catch the dirt, constitutes an effective wedge in forcing its way 
and stout claws, supply the means by which the motive power is 
applied, and serve to force the earth away laterally to admit the 
