36 CHARACTERS OF T. SWAINSONI AND VARIETIES 



CH. SP. a. SWAINSONI. $ 9 Olivaceus, cauda concolore ; 

 subtus albus, lateribus griseo-olivaceis, pectore, jugulo, palpebris, 

 cum lateribus capitis et colli subflavicantibus, pectore et jugulo 

 maculis magnis fuscis notatis. 



Above clear olivaceous, of exactly the same shade over all the upper 

 parts ; below white, strongly shaded with olive-gray on the sides and flanks, . 

 the throat, breast, and sides of the neck and head strongly tinged with yel- 

 lowish, the fore parts, excepting the throat, marked with numerous large, 

 broad, dusky spots, which extend backward on the breast and belly, there 

 rather paler, and more like the olivaceous of the upper parts. Edges of 

 eyelids yellowish, forming a strong orbital ring ; lores the same. Mouth 

 yellow ; bill blackish, the basal half of lower maudible pale ; iris dark 

 brown ; feet pale ashy-brown. Length of $ , 7-7| ; extent, 12-12 ; wing, 

 about 4; tail, about 3; bill, |; tarsus, I fa. $ averaging smaller 6-f- 

 extent, 1H-J- ; &c. 



&. ALICIA. $ 9 Olivaceus, lateribus capitis concoloribus, 

 jugulo vix flavido-tincto. Major; rostro longiore, graciliore; long. 

 tot. 7J-8 $ alar. exp. 12J-13Jj ala 4+, cauda 3+. 



Similar to sivainsoni; sides of the head like the back, or merely more gray- 

 ish ; the distinct yellowish orbital ring and lores of swainsoni not being seen, 

 or but faintly indicated. Breast but slightly tinged with yellowish. Rather 

 larger than sivainsoni, the length averaging rather over the maximum of the 

 latter, sometimes exceeding 8 inches, and other dimensions to correspond 

 bill rather over an inch, and comparatively slenderer than in sivainsoni. 



c. USTULATUS. $ 2 Rufo-olivaceus j cceteris T. sicainson 

 sat similis. 



This form is entirely like swainsoni proper, excepting in a rufous shade o 

 the olive of the upper parts approaching that of fuscescens, from, which it is 

 distinguished by the different tone and pattern of the coloration of the 

 under parts. These characters, which it shares with swainsoni, distinguish 

 it from alicice, no less than does the shade of the upper parts. It is simply 

 the more rufous phase of swainsoni from the northwest coast region. 



T. alicicK is more decidedly different from swainsoni in the characters note 

 above, and is held by many excellent ornithologists as a distinct species. 

 The interrelationships are treated in my " Birds of the Northwest ", and 

 more fully in the " History of North American Birds ". 



ONE of the most peculiar traits of the Olive backed Thrash 

 is its erratic disposition. If not a greater vagabond than the 

 Robin itself, this Thrush commonly wanders further south than 

 any of its relatives ; its journeying into distant portions of South 

 America being conspicuous. While the rest of our Thrushes 

 which leave the United States in the autumn rarely if ever pene- 



