54 PROCEEDINGS OP THE 



Lopez, Otto Behr. 



The records of arrival of all the species at the stations within 

 ten miles of Philadelphia will be found in the accompaning 

 tables, while the large schedule contains the arrivals of the more 

 common species at the remaining stations. I am much indebted 

 to Mr. Paul L. Lorrilliere for aid in compiling these data. 



The method explained on page 48 of Cassinia for 1904, seems 

 to furnish the most accurate record of the arrival of a species in 

 a given district, that can be obtained from a combination of field 

 observations. Instead of expecting our records to show a i;ni- 

 form date of arrival at all stations within a radius of say ten 

 miles, it seems more likely that a correct statement of the pro- 

 gress of migration of a species will be that individuals arrived at 

 certain stations on such and such dates and that the bulk move- 

 ment occurred on a later date indicated by the simultaneous 

 arrival at a large number of stations. Sometimes this bulk 

 movement is not so well marked, which would seem to indicate 

 a continuous migration of the species covering a greater period. 

 A few examples from the 1905 records will serve to illustrate 

 these remarks. 



Chimney Sufifl. Scarlet Tanager. 



April 13. Frankford. April 21. Collingdale. 



April 18. Bryn Mawr and May 2. Media. 



Lansdowne. May 3. Lansdowne, Olney, 

 April 19. Bordentown. Westtown, Knowlton. 



April 20. Nine stations. I\Iay 5. Four stations. 



April 21. Eighteen stations. May 6. Six stations. 



May 7. Seven stations. 



Ovenhird. Wood Thrush. 



April 25. West Philadelphia, April 23. Germantown. 



Concordville. April 24. Oak Lane. 



April 26. Kennett. April 25. Media, Haverford. 



April 27. Swarthmore,' West- April 26. Frankford. 



town. April 27. Olney, Bordentown. 



April 28. Haverford. April 28. Six stations. 



April 29. Nine stations. April 29. One station. 



April 30. Twelve stations. April 30. Eight stations. 



