THE HORNED EARK. 



199 



THE Horned Lark bears the reputation of being the most plastic of 

 American species — the Song Sparrow (Melospica cinerea) alone competing 

 with it in this respect. A recent monograph by Mr. Harry C. Oberholser^ 

 enumerates twenty-two forms, of which sixteen are described as North 

 American, and five Mexican, beside one from Colombia and another (0. a. 

 flava) from Eurasia. Of this number the majority occur west of the Miss- 

 issippi River, where climatic conditions are more sharply differentiated, and 

 where, especially in the southwest, the situation admits of that permanent 

 residence which is almost essential to the marked development of subspecific 

 forms. Doubtless other forms will be elaborated, and perhaps some of the 

 distinctions here pointed out will prove inconstant, and the names proposed 



Taken in Colorado. 



Plioto by E. R. IVarren 



HORNED I„'\RK— MALE; = 



untenable; but the fact remains that Mr. Oberholser has done a splendid 

 piece of work, and one which serves to renew the fascination of the old prob- 

 lem of the influence of environment upon the origin of species. 



There is much to be done in Ohio in accurately determining the mutual 

 relations and the distribution of the three forms which occur here in winter. 

 The problem is complicated by the large number of intermediate forms which 

 are to be found. Indeed it is scarcely too much to say that no two Horned 

 Larks look exactly alike. Typical specimens of each subspecies may be found 

 during any season, but the majority of all birds taken will prove to be puz- 

 zling intergrades. The reason for this I conjecture to be as follows: Oto- 

 coris alpestris (or more properly, 0. alpcstris alpcstris) attains its maximum 



1 A Review of the Larks of the Genus Otocoris (Proceedings of U. S. Nat'l Museum, Vol XXIV. 



2 This series of pictures taken by Mr. Warren in midwinter at Colorado Springs and represents 

 (;. a. leucolacma (Coues) or, possibly, O. a. hoyti Bishop. In either case the differences between them 

 and our local species are too slight to he noticeable in a black and white reproduction. 



