I A Brewster on Bird^ of Berkshire County. Mass. [Januiuy 



Swifts, which were careering about close over the bushes and turf, 

 evidently reaping a rich harvest of insects. The most abundant 

 species was the Snowbird, more numerous here than elsewhere 

 on Graylock. This bird seems to have a particular fondness for 

 hm-e mountain tops of whatever altitude. 



We left the summit at about two o'clock and spent a long after- 

 noon in the descent, repeating many of the episodes of the morning, 

 finding nothing not already mentioned, and reaching the base 

 barely in time to hear the Bobolinks bid good night to the sun. 

 Looking back at the rosy haze fast deepening into purple shadows 

 under the brow of the mountain, it was hard to realize that the 

 clay's experience had not been a delightful dream. 



Reccipitidation. Judging from what I saw of it, the low 

 country (i.e.. the valleys along the streams and the hills of moder- 

 ate elevation) of northern Berkshire County has a nearly pure 

 Alleghanian Fauna. Indeed I failed to find there a single bird 

 which does not breed regularly within ten miles of Cambridge, 

 although a few species common and universall}^ distributed in the 

 eastern portion of the State were apparently absent. Conspicu- 

 ous among these were HarporhyncJuts riifus^ Dendroeca pinus^ 

 and Plpilo ervthrophthalmtis. Minor differences, due possibly 

 to local causes, were the scarcity oi Hehui?ithophila rttjicapilla, 

 Geothlvpis trichas^ and Melospiza palustris, and the restric- 

 tion of Ttii-dus inustelinus^ Pyranga r?tbra, and Goniaphca 

 hidoviciana to the mountain sides or their intersecting water 

 courses. But except for these slight differences the birds met 

 with during a morning walk along the roads and through the 

 woods and meadows about Williamstown or Adams* were 

 identical with those which occur almost e^'erywhere in Middlesex 

 County. 



At the base of the mountains or rather a little way up oh their 

 sides, and in such elevated glens as that at the head of the "Hop- 

 per," one would indeed find a few Canadian forms, sucli as 

 Dendrceca maculosa, Geothlypis Philadelphia, and Junco 

 hie?7ialis ; but it was only a sprinkling, for the border line, at 



* Mr. Allen tells me that he has seen Snowbirds in July on the outskirts of North 

 Adams, but it must be remembered that they can descend from the neighboring moun- 

 tains in a few minutes and doubtless they, with most of the other mountain birds, do 

 actually visit the low country as soon as their young are able to fly, and long before 

 the arrival of the northern migrants. 



