1908.1 



NATURAL SCIENCES OF PHILADELPHIA. 



141 



\SoZ 



29, the Fox Sparrow being a characteristic species of the first move- 

 ment, the Chipping Sparrow and Phoebe of the other two. April was 

 but httle above the normal temperature, the marked increase being on 

 the 11th, 23d and 30th, with corresponding migration on April 12, 13, 

 21-22, 26, and May 1. The May movement continued until the 4th, 

 broken on the 3d by rain. 



only equalled once in the previous thirty years. There was only one 

 well-marked wave during the month, on the 15th, following the high 

 temperature which culminated on the 14th. 



In April the coincidence of migration waves and increases in temper- 

 ature will be noticed on April 9, 19, 25 and 30, with the great May 

 movements on May 5 and 8. 



