188 ^'EW YORK ZOOLOGICAL SOCIETY. 



Turning back to South America and starting- northward again 

 via the West Indies, we find a second hne of distribution of these 

 owls, with distinct island forms on Margarita, Guadeloupe, Anti- 

 gua, and Hayti. Finally, the most northern link in the chain, in 

 the Bahamas and southern Florida, is the Florida Burrowing Owl, 

 S. c. floridana Ridgw. This differs from the Western race 



THE WESTERN BUKKOWING OWL. 



in being gray instead of earthy brown or sand color, the greater 

 humidity of its habitat and of that of its island progenitors ac- 

 counting for its darker coloration. 



Wherever the Burrowing Owl is found, it is wholly terrestrial 

 in habit, and subterranean in its nesting. This unusual environ- 

 ment has affected its structure and appearance ; the diurnal life 

 having perhaps brought about the degeneration of the facial disk, 

 which is markedly imperfect. The legs have greatly increased in 

 length and the feathers on the toes and tarsus have either dis- 

 appeared or degenerated into bristles. 



The Western owl usually occupies the deserted hole of a prairie- 

 dog ; farther south, the burrows of the large iguana lizards are 

 sometimes pre-empted, and in South America, armadillos and 

 vizcachas are often the original architects of the owl's burrow. 



But whenever dependent upon their own exertions for a home, 

 these owls, whether of the Western or Florida race, show them- 

 selves to be expert sappers and miners. The birds from the 

 latter region, indeed, must always dig their own burrows, as there 

 are no native fossorial mammals or reptiles of large size to im- 



