IV PREFACE. 



regarded by all ornithologists as a distinct order, and the 

 highest of the class. But in the present volume a general 

 scheme of classification became a necessity : the arrangement 

 hitherto adopted in the majority of works on Indian Ornith- 

 ology Legge's ' Birds of Ceylon ' and Oates's ' Birds of 

 Burmah' being the most important exceptions has been 

 that of Jerdon's great work, and was taken from G. B. 

 Gray's, which again was but slightly modified from that of 

 Cuvier. This classification, proposed in the early part of 

 the present century, when the anatomy of birds had received 

 but little attention, was founded exclusively on the characters 

 of the beak and feet. It was soon found that there were 

 defects in the Cuvierian system, one of the leaders in the 

 path of reform being Edward Bly th, the pioneer of Indian 

 scientific ornithology ; but it was long before a satisfactory 

 natural system could be devised, and even now birds are by 

 no means so clearly arranged, or divided into orders so well 

 defined, as mammals and reptiles are. Still some of the 

 later attempts to arrange the intricate groups of birds have 

 been fairly successful in consequence of their depending not 

 on one or two characters but on several, of their taking into 

 consideration both internal anatomy and external structure, 

 and of their making use of such clues to affinity as are 

 afforded by nidification, oology, and the changes of plumage 

 in the young. 



The system adopted in the present work is, in the main, 

 identical with those of Sharpe and Gadow, and differs in no 

 important point from the classifications of Sclater and 

 Newton. References will be found on page 15. The chief 

 difference between the plan here followed and those proposed 

 by the ornithologists named, is that no attempt has been 

 made in the present work to arrange in larger categories the 

 groups here termed orders. This is due to the circumstance 

 that there is a much wider general agreement as to the 

 distinctness of the smaller ordinal or subordinal groups 

 than as to their relations to each other. 



The principal anatomical characters by which the different 

 orders are distinguished are furnished by the bones of the 

 palate, shoulder-girdle and sternum, and the vertebrae ; by 

 the occurrence of cseca in the intestines, the presence or 

 absence of particular muscles in the thigh, and the characters 

 of the deep plantar tendons. Amongst the external cha- 

 racters, pterylosis, or the disposition of the feathers with 

 regard to the clad and naked tracts of the body (pteryla and 



