'1*12. Brewster on Robin Roosts. [October 



Mr. Batchelder visited the Norton colony before daybreak 

 on the morning of July S, 1S90, to see the birds go out. His 

 notes describe this experience in the following words: 



" It was a warm morning, with a few thin clouds, and a moon 

 at the third quarter in the meridian, at three A. M. when I reached 

 the ground. There was hardly a trace of dawn in the east, 

 but one or two Robins had begun singing. At 3.06 there was a 

 chorus singing, so many birds that it was hard to distinguish any 

 individual's song ; it did not seem as if they sang with full power. 

 At 3.16 I heard Robins singing in the trees on Divinity Avenue 

 and probably, too, beyond the Museum. At 3.29 three birds left 

 the roost. By this time there was so much daylight that the 

 moon hardly cast any shadow. At 3.34 one more bird left ; by 

 3.39, twenty had left; 3.41, thirty; 3.44, sixty; 3.46, ninety; 

 3.47, one hundred; 3-49;}, one hundred and fifty; 3.5 1^, two 

 hundred; 3.54, two hundred and fifty; 3.56^, three hundred; 

 4.00, three hundred and forty ; 4.02, three hundred and fifty ; 4.05, 

 three hundred and sixty ; 4. 14, three hundred and seventy-five; 

 4.16 three hundred and eighty ; 4.19, three hundred and eighty- 

 live. At 4.20 it was bright daylight. By this time light fleecy 

 clouds covered thinly most of the sky, and a cool west wind had 

 risen. The Robins, most of them, scattered gradually among 

 the trees adjoining the roost before they finally flew off", and this 

 together with the fact that when they left they usually flew low, 

 diving down nearly to the ground at the beginning of the flight, 

 made it difficult to count the departures ; probably many got 

 away without my seeing them in the dim twilight. A consider- 

 able portion of them stopped to feed in the ball-field before going 

 away ; sometimes one of these would fly up into the trees again 

 before leaving. At 4.20 the roost was pretty nearly deserted, but 

 tor perhaps a hundred yards around Robins were to be seen in 

 the woods, mostly feeding on the ground ; I should think there 

 must have been a hundred of them." 



There is much about the flight to the roost which will remind 

 the reader of migration. The preliminary restlessness and gath- 

 ering of the scattered birds ; the excitement caused by the pas- 

 sage of other tlocks ; the wide spread of the infection; and the 

 brief time in whiph a considerable area is practically drained of 

 its entire Robin population ; — all these are familiar features to 

 one who has studied the phenomena of migration. As with the 



