FAM. REGULID& 
BY C. E. HELLMAYR 
Subfam. Regulinze Gadow, Cat. Birds Brit. Mus. Vol. 8, 1883, pp. 79-87. 
Subfam. Regulinz and Polioptilinz Hellmayr, Tierreich, Lief. 18, 1903, pp. 2-29. 
Subfam. Sylviinz (part.) and Polioptilinze Ridgway, Birds Middle- and North America, Pt.3 (= Bull. 
U.S. Nat. Mus. no. 50), 1904, pp. 698-736. 
Characters. Bill, though variable in length, always shorter than head, slender, rather 
broad and depressed at base, where it is wider than deep; culmen distinctly ridged, straight 
for about one-third or half of its length, decidedly decurved terminally; commissure straight, 
with or without subterminal notch; gonys slightly convex or nearly straight, slightly ascending 
terminally. Nostrils wholly or partly exposed, longitudinal, operculate, sometimes partly 
covered by antrorse bristly latero-frontal plumules. Rictal bristles moderately developed, 
rather soft. Wings rather long, but rounded at tip; fourth and fifth, or fourth, fifth and sixth 
primaries longest; first primary one-third or half as long as second. Tail variable in length and 
shape, the rectrices usually rounded, in one genus, Regzlus, with somewhat pointed tips. 
Tarsus longer than middle toe with claw, acrotarsium scutellate or booted; lateral toes about 
equal in length; hallux equal in length to lateral toes, but stouter, with the claw more strongly 
arched; basal phalanx of middle toe coherent for most of its length to outer toe. 
Coloration very variable. Above olive-green, grey or bluish grey (wings and tail, 
sometimes also crown, black in Polioptila; the crown with a red, orange or yellow patch in 
Regulus, or at least different from colour of back, in Leftopoecile and Lophobasileus, in both 
of which the lower rump is light blue); under parts whitish, yellowish or pale greyish, with 
vinaceous and pale blue tints on throat, chest and sides in Leptopoecile and Lophobasileus. Sexes 
not very different, young generally like the females, never spotted or streaked. 
