232 BULLETIN 186, UNITED STATES NATIONAL MUSEUM 



and now deposited in Stockholm. If my surmise be correct, Gylden- 

 stolpe's repetition of the record in 1920 can be explained only as an 

 oversight. Up to now the species is not definitely known nearer our 

 area than Mae Tha Khwae in the Rahaeng district, whence it has been 

 recorded by Chasen and Boden Kloss as Picus viridanus viridanus 

 (Journ. Siam Soc. Nat. Hist. Suppl., 1928, p. 170), later corrected to 

 P. myrmecophoneus {ibid., 1932, p. 235). 



PICUS CANUS HESSEI Gyldenstolpe 



Thai Black-naped Green Woodpecker 



Picus canus hessei Gyldenstolpe, Orn. Monatsb., vol. 24, 1916, pp. 28-29 (Pha 



Kho and Den Chai, northern Thailand). 

 Picus canus occipitalis, Gyldenstolpe, Kungl. Svenska Vet.-Akad. Handl., 1913, 



p. 47 (Den Chai, Mae Raem, "Vang Nun") ; Journ. Nat. Hist. Soc. Siam, 



1915, p. 229 (listed). 

 Picus canus hessei, Gyldenstolpe, Kungl. Svenska Vet.-Akad. Handl., 1916, p. 



89 (Khun Tan, Pha Kho, Pang Hua Phong, Den Chai) ; Ibis, 1920, p. 599 



("Northern parts of the country"). — Deiqnan, Journ. Siam Soc. Nat. Hist. 



Suppl., 1931, p. 156 (Doi Suthep, Chiang Mai) ; 1936, p. 96 (Doi Suthep, 



Chiang Mai).— Riley, U. S. Nat. Mus. Bull. 172, 1938, p. 214 (Chiang Dao, 



Mae Lang valley, Huai Mae Sae). 



The black-naped green woodpecker is uncommon but generally dis- 

 tributed throughout the northern provinces at low elevations. Eisen- 

 hofer sent to Hannover an undated female from "Siam" and a male 

 taken at Den Chai, February 10, 1912; to Stockholm, two females 

 collected at Khun Tan in 1913. I have examples from Doi Suthep, 

 Ban Muang Sum, and Ban Huai Ki. 



Gyldenstolpe reported (1913) not only that this was one of the 

 commonest woodpeckers in the dry forests of Phrae Province but also 

 that it was "very abundant" at Den Chai, Mae Raem, and "Vang 

 Nun." I never succeeded in finding it even common anywhere in 

 our area and suggest that at least half of the birds observed by 

 Gyldenstolpe were of the nearly related form, P. v. eisenhoferi, a 

 species of precisely similar habits and habitat and at that period still 

 unknown to him. In the neighborhood of Chiang Mai hessei was un- 

 common in bamboo and deciduous forest at the foot and on the lower 

 slopes of Doi Suthep, rare in semideciduous jungle as high as 3,200 

 feet. My specimen from Ban Muang Sum was collected in pine- 

 forest on one of the low hills at the base of Doi Pha Horn Pok. 

 Where eisenhoferi occurs we may expect to find hessei also; in fact, 

 so close is the agreement in habits and preferred environment between 

 these two that their mutual uncommonness may well be explicable by 

 the competition between two closely allied species (with nearly identi- 

 cal survival requirements) for possession of a single ecological niche. 



