Wood-Thrush 517 
and rather carelessly and untidily constructed of sticks 
on the outside and coarse grasses within, and has no 
further lining. It is somewhat shallow and flat. The 
eggs, nearly always four in number, are greyish-white, 
splashed to a varying extent with rusty-brown and pale 
lilac. They measure about °95 x ‘68. Gale found 
fresh eggs between May 20th and June 25th, and this 
agrees with the observations of other naturalists. 
Genus HYLOCICHLA. 
Bill moderate, rather weak ; wings long and pointed, outer primary 
very short and spurious ; tail always very clearly shorter than the 
wing, about even ; tarsus rather long and slender, always exceeding 
the middle toe and claw; plumage plain brown above, spotted or 
streaked below on a white or yellowish-white ground ; never any blue. 
A considerable North American genus, closely allied to the true 
Thrushes (Turdus) of the Old World. Five species and a good many 
additional subspecies occur in the United States. H. guttata pallast 
may possibly occur in Colorado, so it is here included in the key. 
Kery oF THE SPECIES. 
A. Spots on the lower surface very distinct and extending on to 
the flanks. H. mustelina, p. 517. 
B. Spots on the lower surface less distinct and not extending on 
to the flanks. 
a. Upper-parts the same colour throughout. 
a A distinct buffy ring round the eye. H. u. swainsoni, p. 519. 
b! No buffy ring round the eye. H. f. salicicola, p. 518. 
b. Rump and tail with a distinct rufous shade contrasting with 
the olive back 
at Larger—wing over 3-55. 
a? More richly coloured, especially the rufous of the tail. 
H. g. pallasi. 
b? Duller and less richly coloured. 4H. g. auduboni, p. 521. 
bt Smaller—wing under 3-50. H. guttata, p. 521. 
Wood-Thrush. Hylocichla mustelina. 
A.O.U. Checklist no 755—Colorado Record—Henderson 05, p. 42. 
Description.—Adult—Above head and back cinnamon-brown, fading 
to olive-brown on the rump, tail and wings; a white orbital ring ; 
below white, marked on the breast and flanks with large well-defined 
