1921 



BIRDS OF MONTANA 



93 



of "Slay, when the first brood is on the wing, and the middle of June when the 

 second begins. Very few nests, however, seem to be dated between the middle 

 of May and the middle of June, which would indicate that the few found at that 

 season are late stragglers of the first brood. 



Fig. 21. Fkmalk Dkskkt Hokxkd Lark on hek ne«t; Duttox. Photo by 

 A. D. Dubois. 



183. 



Otocoris alpestris merrilli Dwight 

 Dusky Horned Lark 



Summer resident of plains and open grass land in northwestern Montana. 

 Breeds at Missoula and is a permanent resident there (Kittredge, MS). Listed 

 by Sloanaker (MS) as the breeding form at Flathead Lake. Sillowaj^ (1901a, 

 p. 56) considered the subspecies at that point to be Icucolaema. Leucolaema i& 

 listed as breeding in the Bitterroot Valley also (Bailey, ^IS). Leucolaema does 

 occur on the west side of the divide, and has been taken at Missoula, March 25, in 

 a flock of merrilli (Kittredge, IMS), but it seems quite probable that nierrilli is 

 the prevailing breeding form, though many of the birds in this region are prol)- 

 ably intergrades. I secured a breeding bird at Silver Bow, just west of the di- 

 vide, which proved to be leucolaema. This was to be expected, however, as the 

 grass area where this bird was secured actually crossed the divide a few miles 

 farther south, and the main part of it lay on the east side, forming the north 

 slope of the Big Hole River. Intergrades between merrilli and leucolaema have 

 been taken in the Gallatin Valley in fall migration (Richmond and Knowlton, 

 1894, p. 304). 



There are no published accounts of the finding of nests of m.errilli in Mon- 

 tana. Young were seen out of the nest June 6 at IMissoula (Kittredge, MS). 



