32 PROCEEDINGS OP THE 



crows arose steadily, section by section. The bare branches of 

 the trees whicli stood out clearly against the western sky but a 

 minute before seemed to be clothed in thick foliage as the mul- 

 titude of birds settled quietly down." 



The evening flight lines converging to the various roosts are a 

 familiar feature of the winter in most of the country districts in 

 the Delaware and Susquehanna valleys. 



Though the flights passing into the nearby roosts have for 

 years given the built-up portions of Philadelphia a wide berth, 

 in old days they seem to have occasionally come into the very 

 heart of the city. A communication made before the Academy 

 of Natural Sciences by John Cassin, January 21, 1862, described 

 a rather unusual occurrence of this kind; and fortunately in the 

 History of North American Birds Dr. Brewer has given us the 

 account as he heard it from Cassin' s lips, though he has some- 

 how transferred the date to April, 1868, a time of year when 

 the Crows have scattered from their winter flocks. 



He says: "On a Sunday morning when Philadelphia was 

 enveloped in a fog so dense and impenetrable that it was hardly 

 possible to distinguish objects across the street, Mr. Cassin'e 

 attention was attracted to an immense accumulation of these 

 birds in Independence Square. The whole park he found to 

 his utter astonishment occupied by an immense army of Crows. 

 They filled all the trees, bending down the overloaded branches, 

 and swarmed over and covered the ground. The entire space 

 seemed alive with Crows. They had evidently become bewild- 

 ered in the fog and had strangely taken refuge in this small park 

 in the very heart of Philadelphia. As if aware of their close 

 proximity to danger, the whole assembly was quiet, orderly, 

 and silent." Scouts from time to time went out and returned as 

 if to get their bearings, and eventually ' ' the whole of the immense 

 congregation, numbering, Mr. Cassin estimated, hundreds of 

 thousands, rose slowly and silently, preceded by their scouts, 

 and moving off in a westerly direction, were soon lost to view." 



For records of the famous old roosts, notably those of Pea 

 Patch and Reedy Islands in the Delaware, we need only refer to 

 the accounts of Wilson and Audubon. Just how man}' other 

 roosts there were in the early days of the past century it is hard 



