108 University of California Publications in Zoology [Vol. 21 



The winter habitats of certain subspecies are still practically 

 unknown, the few winter specimens that have been collected being 

 undoubtedly stragglers from the centers of abundance. Details of 

 distribution are given elsewhere in this paper, under each of the 

 subspecies, but the nature of the several problems may be briefly 

 touched upon here. The winter homes of fulva and canescens are 

 still practically unknown. Megarhynchus appears in numbers in 

 winter in southern California from an unknown breeding ground. 

 Stephemi in departing from its summer habitat in the Sierra Nevada 

 and the higher mountains of southern California does not visit the 

 adjacent valleys, either as a transient or as a winter visitant. It 

 leaves the region absolutely, in a similar manner to the Green-tailed 

 Towhee {Oreospiza chlorura) and the "Wright Flycatcher {Empidonax 

 wrighti) of the same habitat. The latter two species, however, are 

 known as migrants to the southeast, while the route and destination 

 of stephensi, are facts that are still hidden. 



The manner in which megarhynchus, mariposae, and hrevicauda are 

 distributed locally in southern California in winter suggests that the 

 winter homes of the other subspecies may be found by further explor- 

 ing at the proper season those regions whose winter avifaunas are 

 still but slightly known. It may be pointed out, as regards the 

 mountain ranges of southern California, that while we are well 

 acquainted with the summer birds, there are but one or two points 

 where winter collecting or observations have been carried on at all 

 extensively. Judging from the local distribution in winter of certain 

 of the subspecies of Passerellu, it may well be that those races whose 

 winter homes are not known are just as definitely delimited, but in 

 sections from which reports covering the proper season are lacking. 



The accompanying charts (tables 1, 2) are designed to show 

 the winter distribution of the subspecies of Passerella in California. 

 Under each of the several faunal areas are entered the number of 

 specimens examined of each subspecies, taken within the specified 

 areas between October 15 and April 15, and also the percentage of 

 the total Passerella winter population that is formed by each sub- 

 species. The restriction between limited dates is not quite fair, as it 

 throws out a number of specimens of the more southerly wintering 

 subspecies, taken unquestionably in their winter habitats, but some 

 such arbitrary rule seemed necessary to allow for the presence of 

 migrating individuals in the more northern parts of the state. It is 

 also possible that October 15 is a little too early a date to insure the 

 presence of a bird in its winter home in all cases. 



