HORN BILL 435 



of it until 1801, when Latham described the plumage from a 

 specimen in the British Museum, and the first figure of the whole 

 bird, from an example in the Museum at Calcutta, was j)ublished 

 by Hard wi eke in 1823 {Trans. Linn. Soc. xiv. pi. 23). Yet over 

 twenty years elapsed before French naturalists had seen more 

 than its head. Under Rhinoplax Sundevall places the Buceros 

 comatiis of Raffles ; but this would seem to be a wrong position for 

 that species, the type of Bonaparte's genus Berenicornis, since it does 

 not appear to possess a frontlet of solid horn, and Mr. Elliot puts 

 it in the genus Anorrhinus. 



Of other forms of Hornbill there is not room here to treat at 

 length. In some, as the Indian Anthracoceros and the Ethiopian 

 Bycanistes, the epithema grows out in such wise as to make the 

 bird seem as if it had two beaks, one superimposed upon the other. 

 Great as is the wonder which this arouses among stay-at-home 

 ornithologists, it has failed, as in other cases, to excite enough 

 curiosity among those that have opportunities of observation to 

 enable them to provide the least hint as to the use it serves in the 

 bird's economy. In other forms the epithema is hardly developed, 

 and indeed a fairly complete series may be traced from (setting 

 aside Bucorvus) Buceros to certain species of Toccus in which it may 

 be said not to appear. In some of the intermediate forms it is 

 curiously corrugated, and the ridge and furrow surface extends in 

 Cranorrhinus to the mandible. The development, however, of this 

 most characteristic feature of the Family depends in some species, 

 as might be expected, more or less on age and sex ; and, important 

 as it undoubtedly is, too much weight should not be assigned to it 

 or other means of diagnosis neglected on its account. That excel- 

 lent observer Tickell in his manuscript Birds of India (in the library 

 of the Zoological Society of London) divides the Hornbills of that 

 country into two genera only, Buceros and Aceros, remarking that 

 the birds of the former fly by alternately flapping their wings and 

 sailing, while those of the latter fly by regular flapping only.^ 

 Several diff"erences of structure are presented by the sternal 

 apparatus of the vai"ious Bucerotidse, and it is quite possible that 

 these diff'erences may be correlated with Tickell's observations so as 

 to furnish, when more is known about these birds, a better mode of 

 classing them, and the same may be said of those of the African 

 group containing the genus Toccus and its allies. 



As a whole the Hornbills, of which more than 60 species have 

 been described, form a very natural and in some respects an isolated 

 group, placed by Prof. Huxley among his CoccygomorphEe. It has 



^ The noise made by the wings of some of the large species in their flight is 

 compared by Mr. Wallace, in an admirable article on the Family {Intellectual 

 Observer, 1863, pp. 310 et seqq.), to the puffing of a locomotive steam-engine when 

 starting with a train, and can be heard a mile oft". 



