BIRDS OF NORTH AND MIDDLE AMERICA. 683 



Family CHAM^EID^. 



THK WREN-TITS. 



Small sub-terrestrial " ten-primaried " acutiplantar Oscines with 

 the bill much shorter than middle toe without claw, compressed, and 

 strongly curved above; nostrils exposed, operculate; rictal bristles 

 distinct; tarsus much longer than middle toe and claw (nearly twice 

 as long as middle toe without claw); wing short (little more than 

 twice as long as tarsus), excessively rounded, the ninth primary very 

 much shorter than secondaries, the eighth about equal to the first; tail 

 much longer than wing, graduated for more than one-third its length; 

 plumage very lax, of plain uniform colors. 



Bill much shorter than head (length from rictus about equal to mid- 

 dle toe without claw), its greatest depth equal to a little less than half 

 the length of the exposed culmen, its width at base decidedly greater 

 than its depth, but in middle portion (at anterior end of nasal fossae) 

 the width much less than the depth; culmen strongly curved; maxil- 

 lary tomium faintly concave for anterior half, without perceptible 

 subterminal notch; gonys faintly convex, its basal angle directly 

 beneath the anterior end of the nasal fossae; nasal fossse very large, 

 reaching more than one-third the distance from frontal antise to tip 

 of maxilla, entirely unfeathered; nostrils large, occupying lower and 

 lower-anterior portion of nasal fossae, overhung by a broad, convex 

 operculum which (as in Certhiidae) does not reach to anterior end of 

 nasal fossae. Rictal bristles well developed, the latero-frontal bristles 

 less so, although the longer ones reach quite to the anterior end of the 

 nostrils; feathers of chin and upper throat terminated by distinct 

 though fine bristles. Wing rather short, very much rounded; fifth, 

 fourth, and third primaries longest, the tenth about half as long as 

 eighth, the latter about as long as secondaries, the ninth very much 

 shorter. Tail much longer than wing, graduated for nearly half its 

 length, but the two middle pairs of rectrices about equal in length, 

 the third pair but little shorter; rectrices rather narrow, of nearly 

 equal but slightly increasing width to the rounded tip. Tarsus very 

 long' (nearly half as long as wing, about one-third as long as tail); 

 acrotarsium encroaching but little on outer side of tarsus, divided into 

 eight segments, of which the third, fourth, and fifth, from above, are 

 much the longest, each being about equal in length to the distance 

 from nostril to tip of maxilla; middle toe, without claw, more than 

 half as long as tarsus, its basal phalanx adherent for half its length 

 to outer toe, for slightly less to inner toe; outer toe slightly longer 

 than inner, its claw scarcely reaching to base of middle claw, that of 

 the inner toe falling decidedly short; hallux about equal in length to 

 inner toe but much stouter, its claw decidedly shorter than the digit. 



