Notes on the Plumage of North American Birds 363 



Four races of this species are recognized, one of them confined to north- 

 eastern Mexico. The typical form {T. I. ludovicianus) inhabits the eastern 

 United States. In peninsular Florida it is replaced by a large, dark race, the 

 Florida Wren {T. I. miamensis), and in the lower Rio Grande Valley, Texas, 

 and adjacent parts of Mexico by the Lomita Wren (T. I. lomitensis), char- 

 acterized by shghtly smaller size and decidedly paler and duller colors. 



Rock Wren (Salpindes obsoletus, Fig. 4). — Young birds in juvenal plumage 

 are unmarked above except for inconspicuous dusky bars on the back, while 

 the underparts are immaculate and purer white than in the adult. In worn 

 summer plumage the adult is usually browner than in the autumn. 



Six forms of the Rock Wren have been differentiated. The typical race 

 (S. 0. obsoletus) is found over a large part of the western United States, while 

 the San Nicolas Rock Wren (5. 0. pulverius), differing in its larger bill and paler 

 coloration, is confined to the small island of San Nicolas off the coast of south- 

 ern California. The remaining four races are Mexican. 



Guadalupe Rock Wren {Salpindes guadeloupensis, Fig. 5). — This Wren, 

 found only on Guadalupe Island, Lower California, is scarcely more than a 

 subspecies of the common Rock Wren. It differs from the latter in darker 

 color, shorter wing and tail and larger bill. Young birds are much darker than 

 those of the typical form. 



Bird-Lore's Seventeenth Christmas Bird Census 



BIRD-LORE'S annual bird census will be taken as usual on Christmas 

 Da)^, or as near that date as circumstances will permit; in no case 

 should it be earlier than December 22nd or later than the 28th, and western 

 observers can hardly hope to wait till the last days and still get their reports in 

 in time for publication. Without wishing to appear ungrateful to those con- 

 tributors who have assisted in making the census so remarkably successful, 

 lack of space compels us to ask each census taker to send only one census. 

 Furthermore, much as we should like to print all the records sent, the number 

 received has grown so large that we shall have to exclude those that do not 

 appear to give a fair representation of the winter bird-life of the locality in 

 which they were made. Lists of the comparatively few species that come to 

 feeding-stations and those seen on walks of but an hour or two are usually 

 very far from representative. A census walk should last four hours at the very 

 least, and an all-day one is far preferable, as^one can then cover more of the 

 different types of country in his vicinity, and thus secure a list more indicative 

 of the birds present. A census covering several days would really be just that 

 much more satisfactory, but, as few of our readers are in a position to take such, 

 we think it better to discourage them, that all the censuses^ may be 

 more comparable. 



