iSg2.1 Mearns on the American Sparrow tiaxvks. 26^ 



In the much too small series of these Hawks before me from 

 South America are several, mostly from the northeast coast, that 

 are probably referable to sparveritis ; but most of them are 

 mixed with the subspecies aiistralis^ found over most of South 

 America. 



Comparative measurements. — Average of lo adult males from north of 

 the latitude of Virginia and Tennessee, including five which nave the 

 rufous crown patch well developed, and five which lack the crown patch 

 or exhibit (in two cases) but a trace of it: wing, 188.0; tail, 127.0; chord 

 ofculmen, 11.8; width of bill at base, lo.o; tarsus, 36.7; middle toe 23.7 

 mm. Average of 10 adult males from Florida and Louisiana, including 

 five having the rufous crown, and five in which it is wanting (in one) or 

 much reduced* : wing 179.0; tail, iiS.o; chord of culmen, I2.i ; width of 

 bill at base, 9.9; tarsus, 34.1 ; middle toe, 22.7 mm. Average of 10 adult 

 females from the eastern United States north of the latitude of Virginia 

 and Tennessee: wing, 196.0; tail, 130.0; chord of culmen, 12.6: width of 

 bill at base, 11. o; tarsus, 35.8; middle toe, 24.3. Average of 10 adult 

 females from Florida: wing, 190.0; tail, 126.0; chord ofculmen, 12.3; 

 width of bill at base, 10.7; tarsus, 34.3; middle toe, 22.2. Average of six 

 adult females from Texas : wing, 200.0; tail, 136.0; chord ofculmen, 12.5; 

 width of bill at base, 10.8; tarsus, 35.8; middle toe, 24.3 mm. 



From the above measin-ements it will be seen that Sparrow 

 Hawks from Florida and Louisiana are considerably smaller than 

 those from the Northern States, while those from Texas are 

 larger than in either of the other series. 



Falco sparverius deserticolus, subsp. nov. 



DESERT SPARROW HAWK. 



Habitat. — Southwestern United States, north to northern 

 California and western Montana, south to Mazatlan in north- 

 western Mexico. 



General characters. — Larger than Eastern sfarverius^W\\\\ relatively 

 longer tail. This is a desert form from the treeless regions of the South- 

 west. It is paler, much more rufous, and with a larger crown patch than 

 in the typical form. The black bars on inner webs of quills do not cross 



* Comparison of the average measurements of five northern and of five southern 

 male Sparrow Hawks having large rufous crown patches with five others from each 

 region in which it is wanting or reduced to a slight trace, shows the measurements to 

 be almost identical, in the two sets of specimens. 



