PBINCIPLES AND PRACTICE OF CLASS'IFICATION. 



65 



- 8'6 



egg. 



of them scarcely pre-liistoric. One of the oldest of these is tl 

 of Madagascar, of which we have not only the hones, but the ^gg 

 Dinornithes of New Zealand, were among the later of these to die, 

 portions of sldn, feathers, etc., of these great creatures having been 

 found. With the Moa-reniains are found those of liarpagornis, a 

 raptorial bird large enough to have preyed upon the Moas. Finally, 

 various birds have been exterminated in historic times, and some of 

 them within the life-time of persons now liviug. The Dodo of 

 Mauritius, Didus ineptus, is the most celebrated (jne of these, of 

 tlie living of wMch we have documentary evidence down to 16S1; 

 tlie Solitaire of Eodriguez, Pezophaps solitariiia, the Geant, Leguatia 

 gigantea, and several others of the same Mascarene group of islands, 

 are in similar case. The Great Auk, Alca impennis, is supposed 

 to have become extinct in 18i4 ; a species of Parrot, Nestor pro- 

 ductiis, was last known to be living in 1851 ; various parr(jts and 

 other birds have likewise disappeared within a very few years. 

 At least one North American bird, the Labrador Duck, Camp- 

 tolmnus lahradorius, seems likely soon to foUow. (A. Newton, 

 Encg. Brit, 9th ed., art. Birds.) 



antic 2Epyornis maximus 

 The immense Moas, or 



§ 



• PRINCIPLES AND PRACTICE OF CLASSIPICATION. 



Having seen ^vliat a Bird is, and how it is distinguished 

 from other animals, our next business is to inquire how birds are 

 related to and distinguished from one another, as the basis of 



Fig. 17. — Restoration of 

 Lfiguatia gigantca. From 

 Packard, after ScMegel. 



Classiflcatloji : a prime object of ornithology, without the attainment of which birds, 

 however pleasing they are to the senses, do not satisfy the mind, which always strives to make 

 orderly disposition of its knowledge, and so discover the reciprocal relations and interdcpen- 

 dencies of the things it kno-ivs. Classification presupposes that there do exist such relations, 

 according to which we may arrange objects in the maimer wliich facilitates their comprehen- 

 sion, by bringing together what is like, and separating what is unlike ; and that such relations 

 are the results of fixed, inevitable law. It is, therefore, 



Taxononty (Gr. rd^is, taxis, arrangement, and vofios, nomos, law), or the rational, 

 lawful disposition of observed facts. Just as taxidermy is the art of fixing a bird's skin in a 

 natural manner, so taxonomy is the science of arranging birds in the most natural manner; 

 in the way that brings out most clearly their natural affinities, and so shows them in their 

 proper relations to each other. TUs is the greatest possible help to the memory in its 

 attempt to retain its hold upon great numbers of facts. But taxonomy, which involves 

 consideration of the greatest problems of ornithology, as of every other branch of liiology 

 (biology being the science of life and living things in general), is beset with the gravest difficul- 

 ties, springing from our defective knowledge. We could only perfect our taxonomy by 

 having before us a specimen of every kind of bird that exists, or ever existed ; and by 

 thoroughly understanding how each is related to and differs from every other one. This is 

 obviously impossible ; in point of fact, we do not know all the birds now living, and only a 

 small number of extinct birds have come to light ; so that many of the most important links 

 in the chain of evidence are missing, and many more cannot be satisfactorily joined together. 

 With these springs of ignorance and sources of error nmst be reckoned also the risk of going 



