1921 BIRDS OF MONTANA 91 



City, March 30, 1901. by Hedges (coll. I'mv. Aloutana'). I am certain that [ 

 have seen many birds of this race just over tlie ^Montana border in Harding 

 County, South Dakota, and T believe that more extensive eollei'ting in eastern 

 Montana will show it to lie not uncommon in hard winters. 



In western Montana it is recorded from the Bitterroot Valle.y, Chief Moun- 

 tain Lake, and the Sun River (Dwight, 1890. \). 143) ; from the Gallatin Valley 

 (Richmond and Knowlton. 1894, p. 304; Saunders. 19na. p. 30); from [)eer 

 Lodge and Jefferson counties (Saunders, lOl'ia. p. 27); from Teton Cuiinty 

 (Saunders, 1914a, p. 135) ; and from the Bitterroot Valley (Bailey. JIS ». I liavi' 

 also seen this form near Helena, and taken it near Livingstone, in Park ( 'oiiiity. 



This subspecies evidently leaves in ^lareh. and arrives probably in Di'cem- 

 ber. Dates are; Tjivingstone, December 9. 1908; Helena, March 2G, 11)11; and 

 Chotenu. .Mai-eh 10, 1912. 



182. Otocoris alpestris leucolaema (Cones) 



De.-^ekt H<ii;.\En I^akk 



An abundant sunuuer resident tlirougliout ;dl (if tlie static except th(> nortli- 

 western portion, wheri' it is ju-obably re|ilacc(l by iii<rriUi. AI! dliscrxcrs men- 

 tion the occurrence of tliis species and most of them regard it as abundant. In 

 the prairie region it is one of the commonest birds, breeding on the di'y. short 

 grass areas, such as occur on the higher benches. In such situations this bird is 

 one of the very few species to be found. In the valleys of the mouutainmis half 

 of the state, it is a little less common. m;iinly because the thy sliort grass areas 

 it ju-efcrs are less common. 



The migrations take place V(^rv early in thi' spring, in f;ict the Ocsei't Iloi-ncd 

 Lark is the first common song bii-d to ari-ive. jn'ecediu^- the Rnliin and Moiuitaiu 

 Bluebird by a week or more. .Mtliough a few individuals winter, it is easy to 

 determine the beginning of the sjiring migration, because the bii-ds alwnys mi- 

 grate in flocks, and are suddenly connnon the first day of their jn'rival. Dates of 

 spring arrival are as follows: Gallatin County, ^larcli 9, 1909; Silver Bow 

 County, JIarch 3, 1910; Helena, :\Iarcli 12, 1911; Choteau, :\Iarch 10. 1912. 

 March 3, 1913. Fall migration is less easily determined, as it is difficult to sep- 

 arate late fall migrants from wintering birds. I believe that in western ^lontana 

 at least fall migration does not entirely cease till nearly the first of January, as 

 my observations have sho\\'n that this form of Horned Lj.rk' is more abundant late 

 in December than in the other two winter montlis. 1 have no definite dates 

 however. The majority of the summer birds are gone by the last of November. 



l\Iost wi-iters are silent about the winter occuri-ence of this bird. In eastern 

 Montana it is undoubtedly commoner in winter than nrrliiohi. In western Mon- 

 tana I do not think this the case. Too little winter collecting has been done to 

 determine this with certainty, but the two forms are not difficult to determine in 

 the field, when observed closely in a good light, for tln' throat of Irtimlnrmn is 

 most intensely .vellow at this season, while that of <ir'ti((il<i is white, mikI sin<-i 

 the birds flock togethei', the diffei'euce in size is usmdly a]ipai-ent. ^ly observa- 

 tions go to show that after the fii'st ef J;iiiuary fbicks nf horned larks are mainly 

 arcflcola with oidv an oce;isional siiecinien of l< ik nhn imi. 



