190 BULLETIN 17 2, UNITED STATES NATIONAL MUSEUM 



It can be distinguished from the other form that sometimes straggles 

 to Siam in the winter by having no subterminal white spot below the 

 black tip of the longer crest feathers. Also, it is a darker bird. 



One of the specimens from Koh Lak is immature. It is nearly full 

 grown and only differs from the adult in being somewhat lighter in 

 color. The bill is considerably^ shorter, however. 



Family BUCEROTIDAE: Hornbills 



BUCEROS RHINOCEROS RHINOCEROS Linnaeus 



Bitcems rhinoceros Linnaeus, Systema naturae, ed. 10, p. 104, 1758 (India; 

 Malacca**). 



Dr. W. L. Abbott collected one male and one female, Endau River, 

 eastern coast of Johore, July 11, 1901. He gives the colors of the 

 soft parts as: Male — iris deep red, eyelids and surrounding skin 

 black; upper mandible, distal half white, basal half yellow, becoming 

 red toward base; lower mandible, distal two-thirds w^hite, basal 

 third yellow; bases of both mandibles black; upper surfaces and sides 

 of casque red, posterior surface black, front surface deep yellow, a 

 narrow black line on sides separates the basal half of the two colors 

 and is continued back between casque and upper mandible, the casque 

 translucent and waxy in appearance, as if modeled in wax; feet pale 

 yellowish green, somewhat dusty, claws pale horn brown, the tips 

 black; weight, 5^ pounds. In the female the iris is pearly white, 

 eyelid black, surrounding naked skin dusky red; bill and casque 

 similar to that of the male, but no narrow black line separates the 

 red and yellow on sides of casque or extends up between the casque 

 and upper mandible; posterior surface of casque red, not black; the 

 red of the casque not so intense as in the male; naked skin of abdomen 

 and under sides of wings dusky greenish; inside of mouth brick red; 

 feet and tarsi as in the male; weight, 4}^ pounds. 



This species ranges from Sumatra and Billiton to the Malay States. 

 Apparently there are no records of this hombill for Peninsular Siam. 

 It may occur occasionally in Patani. 



Robinson *^ states that it is the commonest of the large hornbills in 

 the south of the Peninsula. 



A larger race, B. r. silvestris Vieillot, with a differently shaped 

 casque occurs in Java, and another form, B. r. borneoensis Schlegel and 

 Miillcr, is found in Borneo. 



DICHOCEROS BICORNIS BICORNIS (Linnaeus) 



Buceros hicornis Linnaeus, Systema naturae, ed. 10, p. 104, 1758 (China; probably 

 Indo-China). 



One adult male, Koh Chang, January^ 15, 1926; one adult male and 

 one immature female, Nong Khor, Sriracha, November 15, 16, 1926; 



« Hartert, Nov. Zool., vol. 9, p. 543, 1902. 



♦« The birds of the Malay Peninsula, vol. 2, p. 51, 1928. 



