Physical Features and Habitats 27 
Ee ees et 
Mrs. C. J. Pennock, Miss Josephine Pennock, C. 
B. Ressel, Dr. C. W. Richmond, Alfred D. Sharp- 
les, Robert P. Sharples, Jefferson Shaner, Dr. Wit- 
mer Stone, Wm. M. Swayne, Jr., Dr. B. H. War- 
ren, Ezra Webster and M. B. Worth; for ornith- 
ological notes and comments: Mrs. H. P. Brinton, 
C. G. Burn, J. D. Carter, Miss Sarah C. DeHaven, 
J. B. Gill, Dr. W. L. Hartman, C. J. Hunt, Thos. 
H. Jackson, A. C. Redfield, Isaac G. Roberts, Robt. 
P. Sharples, Dr. Witmer Stone, C. A. Thomas, Dr. 
B. H. Warren, Harry Wilson and others. 
My own observations began in the summer of 
1884, have continued without a break of more than a 
few months at a time, up to the present, and extends 
over the eastern and northeastern parts of the county, 
with short visits to the south-central and extreme 
west. My migration records began in the spring of 
1885 with a few common migrants, have now reach- 
ed the thirty-third year, and I am informed that it is 
the only continuous record for this period in Eastern 
Pennsylvania. However, sometimes during the most 
critical time of bird migration, the period of 
my observation may have been limited to the brief 
time of going to and returning from my work. I 
have therefore reserved the right to eliminate a few 
of my records which according to my judgment are 
not representative of the true period of arrival or 
departure; and it was probably with this in mind 
that prompted the late Prof. W. W. Cooke to write 
me a short time before his death, urging the publica- 
tion of my averages and extreme dates. Also the 
long-term averages taken independently so near 
