30 Pasadena Academy of Sciences. Publication II. 



Groesbeck near Pasadena, March 28 ('97); and three fresh, taken by 

 the same collector on the West Fork of the San Gabriel Canon, June 

 5 ('96). Sets are of three to five eggs, ordinaril}' four. 

 169 — ^5p. Contop-us borealis (Swains.)- 



Olive-sided Flycatcher. 



Common in summer above 3000 feet in the mountains, and during 

 the migrations frequently seen on the lowlands and mesas. This bird 

 is a late arrival in the spring, my earliest record being April 24 ('96). 

 In the fall the latest record was a specimen taken Sept. 26 ('96); both 

 near Pasadena. As this species nests in the tallest coniferous trees 

 the eggs are hard to secure. W. B. Judson took a set of three consid- 

 erably incubated eggs on Mt. Wilson, June 11, '97. Nearl}' fledged 

 young ordinarily appear about the 15th of July. 

 170 — ^62. Contopus richardsonii (Swains.). 



Westerr) Wood Pewee. 



Common summer resident of the canons and coniferous forests up 

 to 7000 feet. During the migrations, more or less common along 

 streams and in wooded localities on the lowlands. My notes give the 

 earliest arrival in the vicinity of Pasadena, April 18 ('95), and the last 

 in the fall, Sept. 30 ('94). Breeds mainly in June. Extremes: Set 3, 

 incubation slight, taken by A. I, McCormick near Los Angeles, May 



25 ('95); and 3, slightly incubated, taken near Pasadena by H. A. 

 Gaylord, July 11 ('94). Sets are of 2 to 4 eggs, mostly 3. 



171 — 4.64. Empidonax difficilis Baird. 



Western Flycatcher. 



Common summer resident of the mountain canons. During the 

 migrations, noted all over the lowlands. My notes, taken in the vicin- 

 ity of Pasadena, show the earliest arrival March 30 ('96), and the last 

 seen in the fall, Oct. 10 ('96). Eggs are laid mostly during the latter 

 part of May. My earliest set was of 4 considerably incubated eggs 

 taken May 11 ('95); and the latest, of 4 slightly incubated eggs taken 

 June 29 ('95). Full sets are almost always of 4. 

 172 — 466. Empidonax iraillii (Aud.). 



Traill's Flycatcher. 



Common in summer in the willow regions of the lowlands. Ar- 

 rives late. My earliest record is May 4 ('95); latest in the fall, Sept. 



26 ('96). Nests mostly in June. Extremes: Set 3, slightly incubated, 

 taken by A. I. McCormick near L,os Angeles, May 25 ('95), and a sim- 

 ilar set taken by H. A. Gaylord near Pasadena, July 11 ('94). Full 

 sets are ordinarily of three eggs. H. Robertson reports several sets of 

 four each. 



173 — 468. Empidonax hammondi (Xantus). 



Hammond's Flycatcber. 

 Common migrant. Most numerous in the spring, when it is ob- 

 served mostly on the mesas along the base of the mountains. From H. 

 A. Gaylord's notes, the earliest spring arrival was April 9 ('96) and 

 the last to depart. May 9 ('96). In the fall I have seen this 'Fly- 

 catcher by the first week in September, and I took a specimen as late 

 as Oct. 30 ('97). 



