SALT MARSH YELLOW-THROAT 261 



^ii^- — 3 to 5, usually 4. The eggs of this subspecies are not so 

 profusely marked and average somewhat smaller than those of the 

 eastern forms ; more of the irregular hair like lines, so common to eggs 

 of the Orioles and Blackbirds, occur in some examples, forming a 

 regular network about the large end, the rest of the egg being almost 

 entirely free from markings. Size; average, .70X.53. 



Nesting Dates. — Tacoma, Wash., May 4, half incubated-June 10, 

 one-third incubated {Bowles). 



Biographical References 



(i) J. C. Merrill, Birds of Fort Klamath, Oregon, Auk, V, 1888, 362. (2) 

 W. L. Finley, Two Oregon Warblers, Condor, VI, 1904, 31. (3) A. W. 

 Johnson, Notes on Unusual Nesting Sites of the Pacific Yellow-throat, Condor, 

 VI, 1904, 129. 



Salt Marsh Yellow-throat 



GEOTHLYPIS TRICHAS SINUOSA Grinnell 



SuhspectHc Characters. — This small race of the Yellow-throat appears to 

 resemble specimens of Geothlypis trichas arizela having the posterior border to 

 the black mask narrower and darker than in occidentalis. It may always be 

 known, however, by its small size. Wing, 2.00; tail, 1.80; bill, .40. 



General Distribution. — Permanent resident of the salt marshes 

 about San Francisco Bay. 



The Bird and its Haunts. — This is not only the smallest of the 

 Yellow-throats, but it has the most restricted range. Walter Fisher 

 (MS.) writes: "This race dwells in the salt marshes surrounding San 

 Francisco Bay, California. These diminutive, rather deeply-colored 

 birds are found in the tules and tall grasses bordering the almost in- 

 numerable sloughs which meander the broad salicornia-covered flats. 

 It is a permanent resident, whereas the Yellow-throat which occurs 

 in fresh-water swamps to the north and south, is a migratory race." 



Eggs. — 4. The eggs of this race resemble in character those of 

 Geothlypis trichas occidentalis. 



Belding's Yellow-throat 



GEOTHLYPIS BELDINGI Ridgway 



Distinguishing Characters. — A black masked Yellow-throat much larger 

 than any member of the G. trichas group, with the mask of the c^ bordered 

 posteriorly by yellow. Length (skin), 5,75; wing, 2.70; tail, 2.40; bill, .60. 



Adult S, Spring. — A broad band across the forehead and on the cheeks 

 and ear-coverts black, bordered behind by yellow ; rest of upperparts, wings and 

 tail olive-green, no white markings ; underparts entirely yellow. In about 



