214 BULLETIlSr 17 2, UNITED STATES NATIONAL MUSEUM 



PICUS CANUS HESSEI Gyldenstolpe 



Picus canus hessei Gyldenstolpe, Orn. Monatsb., 1916, p. 28 (Pak Koh, northern 



Siam) . 

 Gecinus canus microrhynchus Robtnson and Kloss, Bull. Brit. Orn. Club, vol. 40, 



p. 12, 1919 (Koh Lak, southwestern Siam). 



One female, Chieng Dao, January 29, 1932; one female, Melang 

 Valley, January 1, 1933; one male, Huey Me Sae, December 24, 1932; 

 one male, Lomkao, February 20, 1934; one male, Knong Phra, April 

 15, 1929; three females, Kwe Noi, Kanburi, September 20, 1929; two 

 males, Sai Yok, Kanburi, September 23, 1929; two males and two 

 females, Pak Chong, May 9, 1925, December 18, 20, 1926; one male, 

 Sakeo, near Krabin, May 8, 1928; one female, Lamton Lang, May 30, 

 1934; two females, Lat Bua Kao, July 29, August 9, 1929; one female, 

 Chantuk, June 14, 1934; two males, Huey Yang, Sriracha, August 4, 

 1932; two males and three females, Pran, May 26, 28, 1928, April 2-4, 

 1931. 



Apparently there is little difference between specimens from north- 

 ern and eastern Siam, and little or none between the latter and birds 

 from southwestern Siam. 



Four males from northern and western Siam measure: Wing, 

 151-153 (151.5) ; culmen, 40-41.5 (40.7) mm. Six males from central, 

 eastern, and southwestern Siam: Wing, 148-152.5 (150.2); culmen, 

 40-42 (41) mm. Five females from northern and western Siam: 

 Wing, 144-153 (150); culmen, 35.5-41 (38.4) mm. Seven females 

 from eastern and southwestern Siam: Wing, 137-154 (148); culmen, 

 37-40.5 (38.9) mm. 



The two smallest male specimens measured are from Huey Yang, 

 Sriracha, with wings of 137-141 mm, culmens, 38-39 mm, but there are 

 indications in the plumage that they are birds of the year, and their 

 measurements have not been included in the averages above. One 

 of these males (no. 331880) has the rump orange instead of lemon- 

 yellow and the upperparts more of an orange citrine. Both of these 

 immature males resemble the adult, except the lowcrparts have only 

 the chest washed with a lighter greenish yellow, the belly being gray- 

 ish with slightly darker shadow bars; the red on the crown is more 

 restricted, as are the black malar streak and black of the nape. 



The form ranges from northern, central, and southern Burma east 

 to Siam proper, Laos, Cochincliina, and Annam. In Siam it has been 

 recorded from all parts of the country, from the north as far to the 

 southwest as Koh Lak. In Peninsular Siam no form of this species is 

 known, but in the mountains of the Malay States Picvs canus robinsoni 

 (Grant) is found. 



