372 BULLETIN 196, UNITED STATES NATIONAL MUSEUM 



San Quintin); and southwestern California (San Diego, Escondido, 

 Los Angeles, and Santa Barbara). 



The range as outlined is for the entire species of which several sub- 

 species or geographic races are recognized. The plumbeous gnat- 

 catcher (P. m. melanura) occurs from southeastern California, southern 

 Nevada, central Arizona, and the Rio Grande Valley to Chihuahua 

 and Tamaulipas ; the black-tailed gnatcatcher (P. m. calif ornica) occurs 

 in southwestern California and northwestern Lower California; the 

 San Francisquito gnatcatcher (P. m. pontilis) is found in central 

 Lower California; the Margarita gnatcatcher (P. m. margaritae) is 

 found in Lower California from about 29° N. latitude southward; the 

 Sonora gnatcatcher (P. m. lucida) occurs from southeastern California 

 and southern Arizona to central Sonora. 



Egg dates. — Arizona: 17 records, April 10 to July 15; 9 records, April 

 10 to May 4. 



Lower California: 8 records, April 19 to July 5. 



California: 52 records, March 18 to June 19; 26 records, April 14 

 to May 13, indicating the height of the season. 



POLIOPTILA MELANURA MARGARITAE Ridgway 



MARGARITA GNATCATCHER 



HABITS 



In naming this subspecies, Mr. Ridgway (1904, p. 733, footnote) 

 wrote: "The only specimens examined from Margarita Island (two in 

 number) very likely represent a different form; both have decidedly 

 shorter wings and longer bills than specimens from the mainland of 

 Lower California; they have the upper parts decidedly darker, the dull 

 slate color of the pileum contrasting abruptly and strongly with the 

 dull white of the loral region; there is, apparently, a distinct whitish 

 crescentic mark immediately behind the dark grayish auricular region, 

 a feature which I have not been able to find in any specimen of true 

 P. plumbea. Both specimens were skinned from alcohol; one is an 

 immature male, the other probably an adult female. Should the bird 

 from Margarita Island prove to be distinct, I propose for it the name 

 Polioptila margaritae." 



Santa Margarita Island lies close to the Pacific coast of Lower 

 California, toward the southern end of the peninsula, but north of the 

 Cape region. Although this gnatcatcher was described and named 

 from specimens collected on this island, it seems to be well distributed 

 on the mainland of Lower California between latitudes 24°30 / and 29°. 



The only published account of its habits that I can find is the fol- 

 lowing from Griffing Bancroft (1930) : 



