The Yellowthroats 



Nesting. — As in preceding race. 



General Range. — Southern California and southern Arizona (presumably, 

 also, northern Sonora and Chihuahua). 



Distribution in California. — "Common resident on fresh water marshes of the 

 Pacific lowlands of the San Diegan district; San Diego, Orange and Los Angeles Coun- 

 ties northwest to Santa Barbara, and valley of the South Fork of the Kern River, 

 Kern County; also along the lower Colorado River from Riverside Mountain to the 

 Mexican line" — Grinnell (omitting parentheses). 



Authorities. — Grinnell, Condor, vol. iii., 1901, p. 65 (orig. desc. ; type from 

 El Monte); ibid., Univ. Calif. Pub. Zool., vol. xii., 1912, p. 202 (crit. ; desc, etc.). 



No. 98c Salt Marsh Yellowthroat 



A. O. U. No. 68ie. Geothlypis trichas sinuosa Grinnell. 



Description. — Like G. t. scirpicola, but slightly darker throughout, with reduc- 

 tion of the white fillet; averages somewhat less in size than G. t. occidentalis, especially 

 as to length of wing (mm 53). 



Nesting. — As in preceding form. 



Distribution (Wholly contained within California). — Resident in the fresh- 

 water and brackish marshes immediately tributary to San Francisco Bay. 



Authorities. — Grinnell, Condor, vol. iii., 1901, p. 65 (orig. desc; type from 

 Palo Alto); Pac Coast Avifauna, no. II, 1915, p. 151 (status in Calif.); Ray, Condor, 

 vol. xviii., 1916, p. 225 (nesting); Schussler, Condor, vol. xx., 1918, p. 62 (nesting, song, 

 etc.); van Rossem, Condor, vol. xxiv., July, 1922, p. 134 (occurrence at Anaheim Bay, 

 Orange Co., in winter). 



Remarks. — Although the atmosphere of San Francisco Bay is undeniably 

 bracing, its effect upon such forms of animal life as have chosen this region for a per- 

 manent residence appears to be restraining rather than stimulating. Thus, the local 

 races of certain birds, as, Melospiza melodia pusillula and Geothlypis trichas sinuosa 

 are slightly dwarfed in size. The trouble is caused rather by reduced activity than 

 by unfavorable environment; for, as Coues says, "Migration holds species true; local- 

 ization lets them slip." 



A critical study of the two local or sedentary forms, G. t. scirpicola and G. t. 

 sinuosa, will scarcely discover any points of difference from the migrant occidentalis, 

 save those trifling ones of plumage, tone, and wing measurements. But the fault is 

 manifestly our own. Our methods of observation are too crude and our facilities for 

 comparison are too limited. It is impossible but that these separate races which have 

 endured so differently should reflect that diverse experience in modification of song, 

 of feeding habits, of courting and breeding cycles, — in short, in an altered psychology. 

 But all this is too subtle for our detection — so far. 



"CATTAIL Yellowthroat" would be a more appropriate name, 

 if only we had the courage to apply it, because for every pond or swamp 

 in the Southland which can boast the presence of the giant bulrushes 

 (Scirpus lacustris occidentalis and S. calif ornicus) , which alone are properly 

 called tules, there are a dozen where only cattails (Typha latifolia or 



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