88 THE CONDOR Vol. XX 



wing, 90.3 mm. ; tail, 108.2 ; culmen, 12.8 ; tarsus, 27.5 ; hind toe and claw, 19.2 ; 

 length of white spot on inner web of outer rectrix, 31.5. No. 28456, female 

 adult: wing, 84.4 mm.; tail, 100.0; culmen, 13.0; tarsus, 28.0; hind toe and claw, 

 20.7; length of white spot on inner web of outer rectrix, 29.5. The above meas- 

 urements will be best understood when compared with the tables in Swarth's re- 

 vision of the California spotted towhees (Condor, xv, 1913, p. 175). 



In establishing this identification I have had the advantage of the experience 

 of Mr. Harry S. Swarth with this group. He has gone over the material here re- 

 ported upon and has concurred in the above conclusions. 



Sitta carolinensis tenuissima, new subspecies 

 Inyo Slender-billed Nuthatch 



Type. — Male adult, no. 28716, Mus. Vert. Zool. ; Hanaupah Canyon, 8700 feet 

 altitude, Panamint Mountains, Inyo County, California; June 1, 1917; collected 

 by J. Dixon ; orig. no. 6114. 



Diagnostic characters. — Similar to Sitta carolinensis aculeata from west-cen- 

 tral California, but bill much longer and slenderer (see fig. 11), size larger, back 

 of a darker tone of gray, and flanks paler ; similar to S. c. nelsoni from southern 

 Arizona, but bill much slenderer (see fig. 11), and sides, and lower surface gen- 

 erally, whiter. 



JZ*^ 



Fig. 11. Bills of three western subspecies of White-breasted Nut- 

 hatch ( Sitta carolinensis ) ; all natural size. 



a. 8. c. aculeata, $ ad.; no. 5344, Mus. Vert. Zool.; Mt. Diablo, Con- 

 tra Costa Co., Calif.; April 18, 1896. 



b. 8. c. tenuissima, $ ad.; no. 28716, Mus. Vert. Zool.; Panamint 



Mts., Inyo Co., Calif.; June 1, 1917. 



c. 8. c. nelsoni, $ ad.; no. 27781, Mus. Vert. Zool.; Sierra Ancha, 



Gila Co., Ariz.; June 24, 1917. 



Remarks. — A series of 21 specimens of this new nuthatch (nos. 28716-28736, 

 Mus. Vert. Zool.) from the Panamint and White mountains includes eleven 

 young and ten adults. The latter are listed in the. accompanying table of meas- 

 urements. In some respects this race is intermediate between the Rocky Moun- 

 tain form and that of the Pacific coast region, but in the extreme slenderness of 

 bill differs from either. Judging from the table of measurements given by Ridg- 

 way (Birds N. and Mid. Amer., pt. in, 1904, p. 445) the range of S. c. tenuissima 

 is likely to be found to extend north along the western rim of the Great Basin at 

 least to Fort Klamath, Oregon. 



In view of Ridgway's synopsis and descriptions of the previously known 

 forms of Sitta carolinensis (loc. cit., pp. 440-450), it seems unnecessary to go into 

 further comparisons here. 



