90 The Wilson Bulletin— No. 63. 



4, 10(15, one w:is tnkfn. niid in lltOT a few were seen each day from 

 August 2(') to -'.), when tlie last evidently departed. 



IGS. *Dciulroica pciisijiraiiica. — Chestnut-sided Warhler. 



Common sj)ring migrant and reguhir, hut in more limited num- 

 bers, in the fall. May 14, 1905, it was common, but we saw none 

 May 20-21, 1000. Among the otlier extraordinary occurrences of the 

 spring of 1007 was the great numbers of this species noted June 

 1. We estimated the numbers seen that day as 150. In the fall wo 

 noted a few at the beginning and end of our stay, September 4-15. 

 One each day September 3, IS and 10, lOOG, and several were noted 

 daily between August 20 and the time of our dei)arture, September 

 0, 1907. 



109. *Den(li(tica casfainii. — T'>ay-breasted Warbler. 



A common spring and fall migrant. May 14, 1905, it was almost 

 abundant and was certainly the most common warhler migrant on the 

 Point. May 20-21, 190G, was a little late for their normal migration, 

 but the abnormal spring of 1907 saw thera still present in consider- 

 able nunUiers June 1. None were noted May 1-4, 1908. In the fall 

 we have seen them in fair numbers on all of our Sei)tember trips, in 

 1907 as early as August 20. They generally come in company with 

 the Black-polls, which rather outmnnber tliem in abundance, and 

 which they so closely resemble in fall as to make the separation of 

 the two species sometimes most difficult even to the most expert. It 

 is rare, however, though it is sometimes said to occur, that a trace 

 of the ispring buff is not to he observed on the sides of the adults or 

 a warm oclu'aceus suffusion is not noticeable on the sides of the ju- 

 veniles of the species. The lack of the faint streaks on the 

 breast, which usually show up on the Black-poll in life out of all 

 proportion to their Intensity as observed in dry skins, is diagnostic. 

 The under-tail coverts of the Bay-broast are also cream color, while in 

 the Black-poll they are pure white. The color of the feet is said to be 

 of value in separating the .two species, it being stated that, in the 

 Bay-breast these parts are dusky, while in the Black-]ioll they show 

 a more yellowish brown color. This may lie somewhat helpful in 

 fresh birds, but in dry skins the difference, according to our series 

 of specimens, is so slight and variable as to be of little xise in de- 

 termining the specific designation. 



170. *Dru(lro(ca striala. — Black-jioll Warbler. 



The peculiar spring distribution of this l)ird in this and adjoining 

 sections of Michigan was touched upon by the authors in the Auk, 

 1907, p. 140-7. It is a very rare spring migrant at Detroit and, up 

 to 1007, no spring records had been made for the comity. At Port 

 Huron, at the foot of Lake Huron, it is more coimnon. It is abun- 



