T62 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



horizontally oval or subcuneate, with membrane above, behind, and 

 below, but broadest above. Rictal ))riytles obsolete. Wing rather 

 short, rounded (seventh, sixth, and fifth primaries longest and nearly 

 equal, the eighth and fourth but little shorter, ninth not longer than 

 second); wing-tip shorter than length of culmen. Tail short (less than 

 twice as long as tarsus but more than two-thirds as long as wing), 

 rounded, the rectrices broad and rounded at tip. Tarsus long (about 

 twice as long as exposed culmen, much more than one-third as long as 

 wing), slender, its scutella indistinct (sometimes obsolete laterally); mid- 

 dle toe, with claw, decidedly shorter than tarsus, its basal phalanx united 

 for more than half its length to outer toe, for less than half to inner; 

 lateral toes with claws reaching about to base of middle claw; hallux 

 about as long as lateral toes but conspicuously stouter, its claw decidedly 

 shorter than the digit. 



Coloration. — Plain brownish gray, grayish brown, or olive above 

 (the wings with narrow whitish bands in one species); under parts 

 much paler than the upper, sometimes dull white, the throat and a 

 superciliary streak sometimes buffy or rufescent. 



Nidi ficat ion. — Unknown. 



Mange. — Galapagos Archipelago, where represented on all the 

 islands of the group. 



I have long been convinced that Certhidea belonged to the Mniotil- 

 tidas rather than the Ccerebidaj, where it had been placed by Messrs. 

 Sclater and Salvin. This view of its relationships has been confirmed 

 by an examination of its anatomical structure, made at my suggestion 

 by Mr. F. A. Lucas.' 



Owing to their extremely plain coloration, it is very difiScult to con- 

 struct a key to the species of this genus, a difficulty greatl3f enhanced 

 by the fact that I have at the present time only four of the nine known 

 forms before me, while two of the remaining five I have not seen at 

 all. The following attempt is therefore far from satisfactory, but may 

 assist somewhat in the identification of the various forms. 



KEY TO THE SPECIES OP CERTHIDEA. 



a. No whitish wing-bars. 



6. Adult males with throat and superciliary streak ochraoeoua-buft or tawny, 

 c. Darker and more olive above; rectrices very narrowly tipped with pale 

 brownish. 

 d. Less olive above, paler and less olive below; bill never black. (Jervis, 

 Narborough, James, Indefatigable, Albemarle, and Duncan islands. ) 



Certhidea olivacea (p. 763) 

 dd. More olive above, darker and more olive below; bill often black. (Chatham 



Island. ) Certhidea luteola (p. 764) 



cc. Paler and more grayish; rectrices rather broadly tipped with whitish. 

 (Charles Island. ) Certhidea ridgwayi (p. 765) 



' See Lucas, The Anatomy and Affinities of Certhidia (sic); Proc. U. S. Nat. MuB., 

 xvii, 1894, 309, 310. 



