188 NEW YORK ZOOLOGICAL’ ‘SOCIE GRY. 
Turning back to South America and starting northward again 
via the West Indies, we find a second line. 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 BURROWING 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- 
