Classification of Birds. 103 



certain and various tribes of birds, since the time they have, 

 throus^li theirevolution, become diiferentiated from theii-remote 

 reptilian stock, is a fact that it is feared those who attempt 

 their taxonomj do not always keep impressed with sutficieiit 

 strength upon their minds. Consequently we often hear of 

 this classifier's arrangement, and that classifier's arrangement 

 or scheme, just as though no real affinities existed, whereas 

 it is the duty of each and every one attempting a taxonomic 

 scheme to discover precisely how the avian tree has thrown 

 out its branches and its twigs, and, if possible, determine the 

 points from where they sprung. Equally useless is it to 

 attempt a classification of birds by selecting for the purpose 

 the ornis of any particular ai-ea of the earth's surface. Those 

 that enter upon the task by applying to taxonomic ornithology 

 the birds occurring within arbitrary political boundaries 

 as mapped out by man will ftiil utterly, and such a piecemaal 

 provisional classification will, with the greatest certainty, be 

 broken up the moment the first far-seeing taxonomer tests it 

 with the morphological facts gathered from the entire class, 

 both existing and extinct, as far as they are known to science. 

 For this reason we must consider all the classifications of 

 birds up to the present time as being merely provisional, 

 inasmuch as we are yet so far from possessing the necessary 

 knowledge to define the true one, based upon the complete 

 biological history of the class. A study of the various classi- 

 ficatory schemes that have been presented within the last 

 twenty-three centuries will convince any one that there has 

 been just as much of an evolution in this field as there has 

 been in the case of birds themselves. It must be remembered 

 in this connexion that even as early as Aristotelian time birds 

 were classified into groups, and Pliny, adhering to much that 

 had been done five centuries before him, selected only the 

 very obvious characters of the feet for the purpose, which 

 threw all the birds known to him into three divisions, of 

 which a Hawk, a Hen, and a Goose were respectively repre- 

 sentative. Thus were associated the Ducks and Cormorants, 

 the Kails and Kobins — and this is what the feet did. Orni- 

 thology was placed upon a scientific basis about the middle 

 of the seventeenth century through the labours of Willughby 

 and Ray. They were the first to use the two main divisions 

 of Land- and Water-birds, and in subdividing both the bills 

 and feet were used as classificatory characters. For the most 

 part Linnaius followed Ray, and in doing so kept many birds 

 in taxonomic juxtaposition wdiere the affinity was quite 

 remote. Mergansers and Albatrosses were kept togetiier, as 

 were Divers and Gulls — and so much for what bills and feet 



