548 BIRDS OF THE REPUBLIC OF PANAMA PART 2 



through Central America and South America to northern Argentina, 

 Paraguay, and southern Brazil. Two of its geographic races are found 

 in Panama. 



DRYOCOPUS LINEATUS MESORHYNCHUS (Cabanis and Heine) 



Ceophloeus mesorhynchus Cabanis and Heine, Mus. Hein., pt. 4, 1863, Heft. 2, 

 p. 86, (Rio Sarapiqui, Costa Rica.) 



Characters. — Under wing coverts distinctly buff ; the throat blacker, 

 with the white reduced in extent. 



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

 179-189 (184.5), tail 110.4-122.5 (115.0), culmen from base 36.8- 

 43.2 (39.8), tarsus 28.4-31.2 (29.8) mm. 



Females (9 from Panama and Costa Rica), wing 177-189 (181.5), 

 tail 105.1-123.1 (117.4), culmen from base 35.0-41.7 (37.5), tarsus 

 28.2-31.6 (29.5) mm. 



Resident. Uncommon, in western Bocas del Toro. 



The name mesorhynchus covers a transition population, mainly of 

 the Caribbean slope of Costa Rica, between Dry oc opus lineatus similis 

 of northern Central America, which has a lighter colored bill and 

 smaller size, and the following race nuperus, in which the bill is wholly 

 dark, the size larger, and the under wing coverts very pale yellow. 

 In size, mesorhynchus is equal to nuperus. Those that I have seen 

 from Bocas del Toro have the bill dark like similis, but in occasional 

 individuals from Costa Rica it is paler in color. 



This race was recorded first in the Republic by Kennard (Kennard 

 and Peters, Proc. Boston Soc. Nat. Hist., vol. 38, 1928, p. 455), who 

 in 1926 collected 2 females at Almirante on February 17 and 26, and 

 a male at Chiriquicito on March 28. Hasso von Wedel secured others 

 at Changuinola on September 29, and at Fruitdale on May 7, 1928 

 (reported by Peters, Bull Mus. Comp. Zool., vol. 71, 1931, p. 319), 

 and 1 on Western River on July 12, 1928, now in the British Museum 

 in London. Loye Miller in 1936 collected 2 on March 26 and April 2, 

 (in the collections of the University of California at Los Angeles). 

 In my work in 1958, I secured a female on Quebrada Pastores on 

 February 14. One in the Gorgas Memorial Laboratory was taken near 

 Almirante, January 23, 1961. 



From available information this race in Panama is found only in the 

 area from the eastern border of the Laguna de Chiriqui to the Costa 

 Rican boundary at the Rio Sixaola. 



