REVIEWS AND BOOK NOTICES. 547 
with which is discussed the, affinities and alleged points of differ- 
ence between the D. Virginiana of the East and the D. * Califor- 
nica” of the West. The conclusion arrived at is that the two 
forms are specifically identical, — an opinion we had ourselves but 
a short time previously expressed.* Respecting their variations 
Dr. Coues thus remarks: ‘‘ The more specimens I examined, the 
more I was struck with the variations that depend upon sex and 
age, as well as those that different individuals corresponding in 
these conditions present. An examination of these points, in the 
natural history of a single animal, may give results of general 
application; and yet in calling attention to the variability of 
the opossum, I do not wish to be understood as supposing that the 
animal is not as constant as many or most others, for I believe it 
to be no exception to a general standard or average in this respect. 
I doubt that one could study any mammal, as closely as I have 
the opossum, without being similarly impressed” (p.15). To the 
writer of the present notice, who has made individual variation in 
both mammals and birds a subject of special study for several 
years, this is cheering testimony, being corroborative of much that 
he had formerly to support almost alone. + 
The list of birds embraces the names of one hundred and forty- 
two species, with quite extended notes on their habits, and 
memoranda of their times of arrival, breeding, departure, etc., 
rendering it highly satisfactory as a faunal list. There is also an 
‘extended notice (p.34, foot note) of the pteryle of Rallus crepitans. 
A list of the reptiles concludes the first part, and numbers 
eleven species. No species of batrachian was noticed on the island, 
though several were observed on some of the neighboring islands, 
as well as on the adjoining main land. 
Part II begins with an apparently nearly exhaustive list of the 
decapodous crustacea, part of which were obtained by dredging. 
Sado species are enumerated, and one cirriped and one 
gre tracan, accompanied by full notes respecting their rela- 
: s abundance, habits and conditions of occurrence. Most of the 
Lay were determined by Prof. S. I. Smith, and the remainder 
acne Dr. Wm. Stimpson, whose loss to science naturalists 
recently had cause to deplore. The Brachiopoda, next in 
* Bull. Mus. Comp. Z $ „ii ; 
uae Mus, Comp. Sa ech esc ae and Vol. ii, Nos.1 and 3 (Oct. 
