212 BIRDS OF DAMARA LAND. 



As regards the breeding-habits of this species, my own 

 experience fully agrees with the very interesting account 

 given by Dr. Livingstone in ' Missionary Travels,' p. 613. 



[With regard to the difference between the white-cheeked 

 and grey-cheeked specimens of this Hornbill;, the examples 

 contained in Mr. Andersson's collection fully bear out his 

 remarks above recorded. Two of these examples (a white- 

 cheeked bird from Objimbinque, and a grey-cheeked one from 

 Ovampo Land) are preserved in the collection of Mr. R. B. 

 Sharpe ; and as both of these were marked as males by Mr. 

 Andersson (no doubt from dissection), and as both of them, 

 from the character of their bills, are evidently adult birds, it 

 follows that the difference is not due either to age or to sex. 



Professor Sundevall, from his remarks at p. 130 of the ' Ofver- 

 sigt" for 1850, appears to consider the grey plumage of the 

 cheeks to be especially characteristic of what he considers the 

 distinct Caffrarian race, for which he has proposed the specific 

 name of " rufirostris." On the other hand, M. Jules P. Verreaux 

 informs me that he considers that both birds are of one and the 

 same species, and that the pure white on the cheeks and the 

 parts adjacent is a nuptial dress annually assumed and lost by 

 a double seasonal change. 



Which of these opinions is the correct one can probably be 

 only ascertained by further observations on these birds in a state 

 of nature than have yet been made; and it is to be hoped that 

 those who may have the opportunity of making the requisite 

 investigations will give their attention to the elucidation of this 

 somewhat obscure variation. — Ed.] 



