18 



CONCAVE-CASQUED HORNBILL. 



Buceros cavatus. B. subcristatus niger, collo subferrug'meo, rostro 

 jlavescente apice subrubro, galea concava antrorsum obtusa. 



Black Hornbill, with subferruginous neck, yellowish bill with 

 reddish tip, and concave casque obtuse in front. 



Le Calao a casque concave. Levaill. Cat. pi. 3. 4. 5. 6. 



GREATLY allied to the bifid-casqued Hornbill, but 

 differing in colour, and in the rostral casque being 

 truncated in front instead of being produced at the 

 tips into two lengthened processes: the general 

 shape of this part is similar in both species, being 

 longitudinally concave, with a deep middle furrow : 

 in the present species however the base of the bill is 

 not marked as in the preceding with a black bar, 

 and the hind part terminates in a rounded or 

 bulging back, while in the bifid-casqued Hornbill 

 it is flattened on that part : the whole bill, with 

 the casque, is of a whitish colour, tending to 

 brown towards the tip: the face and chin are 

 black; the neck pale ochre-coloured, and the whole 

 remainder of the plumage black: the feathers of 

 the back part of the head are slightly lengthened, 

 and of a narrow shape; forming a slight approach 

 to a pendent crest. The plumage of this bird in 

 its young state differs greatly from that which it 

 exhibits in its advanced or perfect state, being ash- 

 grey, with the neck and breast rufous, and the 

 quill-feathers and lower part of the abdomen black- 

 ish; the bill shorter in proportion, and the casque, 



