Rock-Wren 485 
Family TROGLODYTIDZ. 
The Wrens are all small birds, seldom exceeding six 
inches in length, with generally rather long, slender bills, 
without rictal bristles, and exposed nostrils ; wing rather 
short and rounded, of ten primaries, the tenth (outer) 
about half the length of the ninth ; tail moderate, of twelve 
feathers ; tarsus scutellate, often behind as well as in 
front. 
Key or THE GENERA. 
A. Tail equal to or longer than the wing; only the middle tail- 
feathers barred, the others chiefly dusky. Thryomanes, p. 490. 
B. Tail shorter than the wing. 
a. Outer toe distinctly longer than the inner one. 
at Culmen shorter than the tarsus. Salpinctes, p. 485. 
bt Culmen longer than the tarsus. Catherpes, p. 487. 
b. Outer toe not distinctly longer than the inner one. 
at Back plain or faintly transversely barred. 
a? Tail at least } of wing. Troglodytes, p. 491. 
b? Tail less than 3 of wing. Nannus, p. 493. 
b! Back streaked with white and black. 
a? Bill shorter, culmen less than middle toe and claw. 
Cistothorus, p. 494. 
b? Bill longer, culmen exceeding middle toe and claw. 
Telmatodytes, p. 495. 
Genus SALPINCTES. 
Bill about as long as the head, slender, slightly decurved and acute, 
the culmen shorter than the tarsus; no rictal bristles ; nostril large, 
rather conspicuous with an overhanging scale; wing rounded but 
longer than the tail, which is even and has twelve feathers with rounded 
ends ; tarsus scutellate anteriorly and posteriorly ; outer toe slightly 
longer than the inner one. 
One species only in the United States. 
Rock-Wren. Salpinctes obsoletus. 
A.O.U. Checklist no 715—Colorado Records—Say 23, Vol. ii., p. 4; 
Allen 72, pp. 148, 161; Trippe 74, p. 230; Henshaw 75, p. 179 ; Minot 
80, p. 225 ; Drew 81, p. 88 ; Allen & Brewster 83, p. 154 ; Drew 85, p. 15 ; 
W. G. Smith 86, p. 17; Beckham 87, p. 123; Morrison 88, p. 72; 
Kellogg 90, p. 89; Nixon 90, p. 21; Lowe 92, p. 101; 94, p. 269; 01, 
