5 • FIELD AND FOREST. 



The common winter residents are : 



Ectopistes migratoria, Erismatura rubida, 



Bucephala americana, Antlius ludovicianus, 



Regulus satrapa, Eremophila alpestris, 



Carpodacus purpiireus, Junco hyemalis, 



Spizella monticola, Scolecophagus ferrugineus, 



Mareca americana, Fulix affinis, 

 Aythya americana, " collaris, 



" vallisneria, Bernicla canadensis, 



Anas boschas, Dafila acuta, 



" obscura, Nettion carolinensis, 



Querquedula discors, Bucephala albeola, 



Lophodytes cucullatus, Mergus serrator, 



Chroicocephahis Philadelphia, Larus delawarensis, 



Podiceps holbolli, Podilymbus podiceps. 

 Podiceps cornutus. 



R. W. Shufeldt. 



Notes on the Alpine Insect Fauna of the 

 Rocky Mountains. 



The mountain ranges of the Avorld produce a fliuna of remarkable 

 interest in its bearing upon the discussion of geographical distribution 

 and the existence of varietal forms, which have resulted from the great 

 climatic changes through which the globe has passed. When ijt is 

 found that certain insects occur uniformly in the mountains of Asia, 

 Europe and America at great elevations and in British America at 

 high latitudes, the significance of this fact becomes apparent, and we 

 are led to look for other causes of more importance than slight varia- 

 tions of climate. The influence which the glacial period exerted in 

 causing a change of habit should be regarded as of primary significance 

 in its effect upon the distribution of life. Thus we see certain insects 

 on Mt. Washington, N. H., whicji are lost sight of as we journey 

 westwartl through the great expanse of valley and plain to the foot of 

 the Rocky Mountains ; as we ascend them and approach the verge of 

 the alpine flora, these same species re-appear with wonderful regularity. 



