WHITE-HEADED CACTUS WREN 



g. Larger, length about 142 mm. (5.60 in.); 

 above chestnut; sides of head white 

 conspicuously streaked and under tail 



coverts barred with dark brown . . 



Thryophilus rufalbus castanonotus 



gg. Smaller, length about 126 mm. (5.00 in.) ; 

 above grayish brown; under tail cov- 

 erts plain tawny buff 



Thryophilus modestus elutus 



I. Heleodytes albobrunneus Lawrence 

 White-headed Cactus Wren 



Length 180 mm. (7.10 in.); tail 77 mm. 



(3.00 in.). 



Male. Head, neck, and under parts white; 

 upper parts sooty brown. 



Female. Similar to male, but top of head 

 streaked and tinged with pale grayish brown. 



A large rather long-tailed wren inhabiting 

 chiefly land of a more arid character than that 

 which prevails in the Canal Zone. 



2. Thryophilus castaneus castaneus 

 (Lawrence) 

 Bay Wren 



Sexes alike. Length 135 mm. (5.30 in.); 

 tail 53 mm. (2.10 in.). Top of head, nape and 

 sides of neck black, back and rump bright 

 chestnut; tail black barred with chestnut; wings 

 barred black and chestnut; a narrow white line 

 above the eye; cheeks white streaked with 

 dusky, bordered below by a black line which 

 357 



