70 Bird - Lore 
Number 
PLACE Sisae) | onstegimns sen || 7 eenanogean 
Eastern Nova Scotia................. 3 October 17 October 22, 1894 
ScotchwivalkesINENB srr iene erences 6 October 27 November 13, 1904 
St. Jolhing NE WB. caves sinsce orate eres 3 November 1 November £7, 1894 
Montrealy Canadas cecan. acer eos 8 October 17 October 29, 1895 
Southwestern Maine................ I4 October 29 December 7, 1903 
Southern New Hampshire............ 3 November 5 November 14, 1899 
IN@mUNGIAal We MOeNOIMIS bose oconeescosane 5 November 1 November 20, 1906 
Eastern Massachusetts.............. 19 October 28 November 13, 1894 
Vives Wiisvavsell, ING Wop co cacedoouspee 6 October 25 November 1, 1901 
The “Data in the Biological Survey”’ 
Explanatory note by PROFESSOR COOKE 
sources of the notes on migration that appear from month to month. The 
Biological Survey was established twenty-five years ago, and part of its 
work from the outset has been the accumulating of data on bird distribution 
and migration. The card system is used and each note is entered on a separate 
card. At the present time the “data in the Biological Survey ” are contained on 
about four hundred thousand cards of unpublished notes derived principally from 
the more than two thousand different migration observers who have contributed 
their reports during these twenty-five years. The remainder is derived from 
records of museum specimens and from the field notes of the staff of the Bio- 
logical Survey. 
These original notes are supplemented by many published records. The most 
important ornithological publications have been extracted thoroughly, and 
many notes gathered from the so-called minor publications. About two hundred 
thousand cards of published records are now on hand. The notes from “The Auk’ 
alone required over forty thousand cards. 
The Biological Survey, therefore, has about six hundred thousand notes from 
which to draw for information concerning the distribution and migration of North 
American birds. It follows that on some of the more common birds the records 
must be very voluminous. The migration dates given in this number of Brrp- 
Lore for the Song Sparrow are selected from more than three thousand notes— 
which, if published in full in the most condensed form, would require more than 
forty of Brrp-Lorer’s pages. The records for Chicago occupy only two lines, one 
for arrival in spring and the other for departure in the fall, but these dates are 
selected from 83 records contributed during 26 years by 28 different persons. 
|: may interest the readers of BirD-LoreE to learn something about the 
