LIFE HISTORIES OF NORTH AMERICAN WIU> FOWL. 173 



range in Palaearctic regions than is now known, with a westward 

 migration. 



Egg dates. — Arctic Canada: Nineteen records, June 9 to July 6; 

 ten records, June 15 to 23. 



CHEN HYPERBOREA NIVALIS (J. R. Forster) 

 GREATER SNOW GOOSE 



HABITS 



When I first began to study the distribution of this large sub- 

 species I w^as skeptical as to its status, for it did not seem to have 

 any well-defined breeding range or winter range, and it looked very 

 much as if the large birds could be nothing more than extra large 

 individuals. My confusion w^as due to the fact that I did not know 

 where to draw the line between the greater and the lesser snow 

 geese. I found that my friend Frederic H. Kennard had been 

 studying the same problem for some time, and while he had col- 

 lected considerable data, which he placed at my disposal, he was 

 waiting for additional data before publishing it. 



For the purposes of this life history it will suffice to give merely 

 the general conclusion I have arrived at and a brief statement of 

 the steps which led to them. A collection of the measurements of 

 over 250 birds from various parts of the country, when tabulated 

 according to size, shows very clearly that an extra large subspecies, 

 now called nivalis.^ occupies a very narrow winter range on the 

 Atlantic coast, which it reaches by a decidedly eastern migration 

 route from its breeding range in northern Greenland. All of the 

 largest birds come from extreme eastern localities; I have seen only 

 one bird from the interior that I should call nivalis; that is an im- 

 mature bird in the United States National Museum, labeled Hudson 

 Bay, which, if it came from there, is probably a straggler. All of 

 the birds from Atlantic coast States and Provinces are nivalis., 

 except a few very small ones which are doubtless stragglers from 

 the westward and are referable to hyperborea. The average meas- 

 urements of all the birds from Atlantic coast points, including the 

 small birds referred to above, are decidedly larger than the average 

 measurements of birds from the interior or from the Pacific coast 

 States. 



The average measurements of all the birds from the interior, from 

 Hudson Bay to Texas, agree very closely with the average measure- 

 ments of a series of birds fi'om California. This shows conclusively 

 that the birds of the interior are unquestionably referable to the 

 smaller form, hyperhorea.) and that the larger birds from that region, 

 which have been called nivalis^ are merely large specimens of hyper- 



