Liberia <*- 



this bird may be at once distinguished from the black hornbill by 

 the mottled appearance of the short feathers below the throat. 



The horns on the beaks of these birds vary very much, 

 according to age and sex, in the degree to which the projection 

 of the ridge is developed. In the females and in young males 

 there is very little variation in the rounded outline of the 

 ridge, but in adult males this swells at the sides and develops 

 into a permanent " horn." Both these hornbills, like those of 



302. THE ELATE HORNBILL (CERATOGYMNA ELATA) : YOUNG MALE 



the -genus Bycanistes, utter loud, braying cries, especially whilst 

 flying. Two species of Bycanistes (B. subcylindricus and B. 

 fistulator) exist in Liberia, according to Biittikofer. They are 

 large birds with big casques to the beaks and full crests, the 

 plumage being a boldly contrasted combination of black-bronze- 

 green and pure white, with some grey on the face and crest. 

 Amongst the passerine birds may be noted the presence 

 of many lovely species of Nectariniidce (Sun-birds), a brightly 



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