FAMILY FURNARIIDAE 73 



and reduced spotting in bellulus are so definite, and the geographic 

 separation by the broad area of the lowlands of the lower Atrato 

 Basin so complete, that the two, while allied, are best grouped under 

 separate species names, united in the bond of a superspecies. 



MARGARORNIS RUBIGINOSUS Lawrence: Ruddy Margarornis, 

 Trepador Colorado 



Small ; reddish brown with white throat ; often climb like wood- 

 peckers. 



Description. — Length 150-160 mm. Tail long, graduated, with tip 

 elongated, the projecting shafts flexible, and only slightly stiffened; 

 outer rectrix about three- fourths the length of the central pairs. 

 Adult (sexes alike), crown and hindneck chestnut-brown; forehead 

 slightly paler ; rest of upper surface, including most of wings and 

 tail, cinnamon-rufous ; inner webs and tips of primaries dusky ; side 

 of head, including malar region, wood brown ; slightly marked buff 

 superciliary streak ; chin and throat dull white ; rest of under surface 

 cinnamon-buff, paler centrally, darker on sides and under tail coverts. 

 In the nominate race upper breast spotted with pale buffy white, 

 the spots minutely tipped with black ; paler feathers of lower neck 

 and upper breast barred slightly with dusky ; under wing coverts 

 buff, darker externally, slightly marked with dusky-brown ; inner 

 webs of primaries and secondaries edged narrowly with ochraceous- 

 buff. 



The species is one that is little known in Panama, where it is found 

 in the western mountains, with two subspecies recognized. 



MARGARORNIS RUBIGINOSUS RUBIGINOSUS Lawrence 



Margarornis rtibiginosus Lawrence, Ann. Lye. Nat. Hist. New York, vol. 8, 

 1865, p. 128. (San Jose, Costa Rica.) 



Characters. — Paler rufescent brown on back, wings, and tail; 

 crown somewhat duller ; under surface lighter, more grayish on center 

 of breast and sides ; breast definitely spotted with white. 



A female collected near 2400 meters elevation on the west face of 

 Volcan Baru, March 11, 1965, had the iris dark brown; base of 

 maxilla, including the nasal opercula, fuscous-brown ; rest of maxilla 

 dull Verona brown, darker on the tip of the culmen ; mandible pinkish 

 white ; tarsus, toes, and claws dark grayish brown. 



Measurements. — Males (10 from Chiriqui and Costa Rica), wing 

 74.2-79.0 (77.1), tail 71.8-79.1 (74.3), culmen from base 13.2-14.7 

 (13.9), tarsus 20.0-21.4 (20.5) mm. 



