158 BULLETIN OF THE 



TYRANNIDiE. 



31. Contopus borealis. Occasional in the limber along the ridges, 

 but more plentiful in the mountains to the eastward of the Park. 



32. Contopus virens, var. Richardsoni. Common. Found several 

 nests with half-grown young, July 18 to 23, at Fairplay. Nest placed in 

 the fork of small branches, and quite different from that of C. virens in 

 the eastern States, as are also its notes.* 



33. Empidonax " obscurus." Common in the thick willows' near the 

 streams. Found a nest July 20th containing young but a day or two old, 

 and another the same day with young nearly ready to fly. Nests placed in 

 the forks of branches in dense willow clumps, and much resembled the 

 ordinary nest of Dendroeca cextiua. Bird very shy, hiding in the bushes, 

 thus rendering it very hard to shoot. Rarely seen even when but a few 

 yards distant, often stealing away without coming into view. 



CAPRIMULGID.E. 



34. Chordeiles popetue. Abundant. 



TROCHILIDJE. 



35. Selasphorus platycercus. Abundant. 



PICID^J. 



36. Sphyrapicus varius, var. nuchalis. Common in the mountains 

 near the eastern border of the Park. 



3 7. Sphyrapicus Williamsoni. A few seen, chiefly at the eastern 

 side of the Park. Quite common in the mountains further eastward. 



38. Melanerpes erytkrocephalus. Not common. A few pairs ob- 

 served at Fairplay. 



39. Colaptes mexicanus. Abundant. 



FALCONID.5!. 



40. Falco peregrinus. One specimen was shot at Fairplay, a young 

 bird that came about our camp in pursuit of blackbirds. 



* Specimens of Conlvpus virens from the Rocky Mountains are considerably darker 

 throughout than those from the Atlantic States. They generally lack the white edge to 

 the outer vane of the first primary, usually seen in the latter, though eastern specimens 

 are often without it. The western specimens are less strongly tinged with yellow be- 

 neath, and the axillaries are considerably darker. The greater coverts and secondaries 

 are less broadly edged with white. The lower mandible, instead of being yellow as in 

 eastern summer specimens, appears to be always dusky, — black towards the tip and 

 yellow only at the base. But this feature is also frequently shared by autumnal speci- 

 mens at the East. The whole •difference between the two hence seems to consist in the 

 darker tints of the western form. 



The variety Richardsoni was the only form seen at Denver and Cheyenne, as well as 

 in the mountains, while the specimens from Eastern Kansas were of the eastern type, 

 differing from Massachusetts specimens only iu being somewhat more olivaceous. 



