MANUAL OF NATURAL HISTORY. 35 



be hatched by the heat developed during fermenta- 

 tion, astonish us by their novelty; and amongst 

 other extraordinary habits may rank that of the 

 Bower-birds of the same country, for whose singular 

 bower-like erections it is difficult to determine a use. 

 These, with numberless others, form subjects for 

 pleasing investigation ; and the more such enquiries 

 are pursued, the keener will be the interest taken 

 in them, for truly in nature every charm is really 

 supreme. 



II. CLASS. BIRDS (Aves). 



Body clothed with feathers ; anterior limbs con- 

 structed for flight (with few exceptions) ; bills horny ; 

 feet covered with a scaly skin. 



I. ORDER RAPACIOUS BIRDS (Accipitres). 



Bill strong, upper mandible sharp, pointed, and 

 curving downwards; cutting margins toothed or 

 festooned ; nostrils pierced in a membrane (cere) in- 

 vesting the base of the bill; talons sharp, strong, 

 much hooked ; muscular power great. 



I. SUB-ORDER. DIURNAL RAPACIOUS BIRDS (Diurni). 

 Eyes placed laterally. 



1. FAMILY. Vultures (Vulturidse). Head more or 

 less denuded ; eyes level with surface of 

 cheeks ; bill not toothed, lateral margins of 

 upper mandible rather sinuous, extensively 

 covered with the cere ; tarsi short and covered 



