400 LIFE HISTORIES OF NORTH AMERICAN BIRDS. 



domicile, and as a rule will not leave it, although the way may be left clear 

 for it to do so. Backing up to the extreme end of its burrow, it will strike 

 with beak and claws in defense of its nest. Frequently when within a foot 

 or two of the nest proper, and before it was yet visible the occupant made 

 a rattling noise, produced by the rapid movement of its mandibles, which 

 sounded very much like the warning of the rattlesnake when disturbed; this 

 would easily impose on the average investigator, and proceeding out of the 

 burrow, somewhat muffled and subdued, is very similar indeed to the rattle 

 of the latter. 



The number of eggs laid by the Burrowing Owl varies from six to 

 eleven. From seven to nine are more often found, while sets of ten and 

 eleven are not especially rare, and Mr. Walter E. Bryant, of Oakland, Cali- 

 fornia, found one of twelve near Carson, Nevada. The eggs are usually 

 found in a single layer and disposed in the form of a horseshoe. On two 

 occasions in extra large sets, I found them placed on top of each other. It 

 is astonishing how they manage to cover them . all, but they do, and it is 

 rare to find an addled egg. Both parents assist in incubation, which lasts 

 about three weeks, and but a single brood is raised in a season. A second, 

 and somewhat smaller set is frequently laid in the same burrow or in another 

 close by, if the first eggs are taken. 



The eggs of the Burrowing Owl, after they are washed, are pure white in 

 color, but as taken from the burrow they are usually much soiled by the 

 excrement of the numerous fleas inhabiting these domiciles, and bear then 

 no resemblance to white. They are much more glossy than most Owls' eggs 

 and are usually rounded ovate in shape. The shell is close grained and 

 rather smooth, but in some sets it is strongly granulated. 



The average size of a fine series of these eggs is 31 by 25.5 millimetres, 

 the largest egg of the series measuring 34 by 27 millimetres, the smallest 28 by 

 25 millimetres. 



The type specimen, No. 20578 (PL 12, Fig. 14), from the Bendire col- 

 lection, selected from a set of nine eggs, was taken near Fort Walla Walla, 

 Washington, April 21, 1881. 



141. Speotyto cunicularia floridana Ridgway. 



FLORIDA BURROWING OWL. 



Speotyto cunicularia var. floridana Ridgway, American Sportsman, v, July 4, 1874, 



216. 

 (B — , C — , R 408a, C 488, U 378a.) 



Geographical range : Florida and the adjacent Bahama Islands (New Provi- 

 dence). 



The breeding range of the Florida Burrowing Owl, a variety somewhat 

 lighter colored than the preceding, seems to be confined to the State of 

 Florida and to some of the Bahama Islands. It is an inhabitant of the vast 

 prairie found north of Lake Okechobee and similar localities in other parts 

 of the State. 



