BIRDS OF NOETH AND MIDDLE AMERICA. 425 



AegithaliscnK Ca})anis/' also of southeastern Asia (including- north- 

 ern India), is less nearly related to Pmltriparus^ having the bill very 

 much thicker. It is very near, however, to AcanthiparuH^ from which 

 it otherwise ditl'ers chiefly in st3de of coloration, the pilcum and hind- 

 neck being rufous, in strong contrast with the gray back, und a l)lack 

 patch on the throat, and there is ground for doubt as to wh<^ther the 

 two groups should be separated generically. 



Aegithalos,'' another Pahearctic genus, is still more reuujlely related 

 to Psaltriparux^ having the tail x&ry much longer than the wing and 

 graduated for half its length or more, the bill being short and deep, 

 as in Aegithallscus, but more compressed. 



KEY TO THE SPECIES AND SUBSPECIES OK PSALTRIPARUS. 



a. With black on sides of head. 

 h. Entire side of head black, 

 c. Back, scapulars, and rump decidedly brown or olive. 



d. Back, etc, olive-brown; under parts of body strongly buffy. (Southern 

 Mexico and Guatemala. )..Psaltriparus melanotis melanotis, male (p. 426) 

 dd. Back, etc., olive or grayisli olivt*; under parts df liody dull white, very 

 slightly, if at all, tinged with buff. (Central and western Mexico.) 



Psaltriparus melanotis iulus, male (p. 428) 

 cc. Back, scapulars, and rump olive-gray. (Northern ]\Iexic'o, southwestern 

 Texas, southern New ]Mexi('(), and southern Arizona. ) 



Psaltriparus melanotis lloydi, male (p. 429) 

 hh. Side of head only partly black (the blaek usually confined to a patch on^de 

 of occiput, sometimes continued forward toward eye). 

 c. Back, etc., decidedly brown or olive. 

 (/. Back, etc., olive-brown; under parts of body strongly ])uffy. 



Psaltriparus melanotis melanotis, female (p. 426) 

 dd. Back, etc., olive or grayish (jlive; under {)arts of body dull white or but 



faintly tinged with l)uff Psaltriparus melanotis iulus, female (p. 428) 



cc. Back, etc., olive-gray. 



Psaltriparus melanotis lloydi, female and young male (p. 480) 

 axx. Without any black on sides of head. 

 6. Pileum gray, like l)ack, etc. 



c. Averaging whiter beneath (especially on throat) and more olive-gray on 



back. . . )Psaltriparus melanotis lloydi, some females and young (pj). 429, 430) 



cc. Averaging more grayish and more uniform ])eneath, with back clearer gray. 



(Arid western United States, from eastern Oregon, Utah, and Wyoming 



to southwestern Texas, southejistern California, and northern parts of 



Sonora and Chihuahua.) Psaltriparus plumbeus (p. 430) 



a Aegithalisciui Cabanis, Mus. Hein., i, 1850, 90 (type, Parus eri/throcephalus 

 Vigors). 



b Aegilhalo.'i Hermann, Obs. Zool., i, 1804, 214 (type, I'ipra cttropua Hermann). 

 Mecistura Leach, Syst. Cat. Mam. and Birds Brit. Mus., 1816, 17 (type, M. vagaa^ 

 Leach = Parus caudatufi Linna-us). Acredula Koch, Bayr. Zool., i, 1816, 199 (type, 

 Parus caudatHS Linnanis). Paroides Brehm, Isis, 1828, 1284 (type, J'ant.'i ca>id<i(n.^ 

 Linnaus). Oritcs (not of Keyserling and Blasius, 1840) Gray, List Gen. Birds, 1841, 

 32 (type, PaniR caudal n.^ Linnieus). See Stejneger, I'roc. U. S. Nat. Mus., ix, 1886, 

 382, 383. 



