132 RiDGWAY on Zoological Nomenclature. 



afford any longer to ignore the existence of subspecies in nature, or 

 to attempt to make ornithological nomenclature simpler than tlie 

 facts of nature which it is intended to discriminate." 



Until the matter shall have been definitely decided by the 

 agreement of leading ornithologists, it may be considered purely 

 optional with a writer what combination of generic, specific, and 

 subspecific names he uses in the case of geographical races of ani- 

 mals, provided, of course, he does no violence to the essential prin- 

 ciples of the nomenclature established by Linnaeus and adopted, 

 with amendments, by the British Association. Linna3us, as well as 

 subsequent authors of the past century, not unfrequently employed 

 a third term for the designation of races or varieties. This prac- 

 tice, however, though not actually prohibited by the Rules of the 

 British Association for the Advancement of Science, such prohibi- 

 tion is implied in the first three lines of the third paragraph uiider 

 § 1 of the rules referred to, which read as follows : " As our subject- 

 matter is confined strictly to the binomial system of nomenclature, or 

 that which indicates species by two Latin words, the one generic, 

 the other specific ; and as this invaluable method originated solely 

 with Linnaeus," etc. At the time Linnaeus wrote, intergradatiun 

 between supposed species was a thing not thought of; therefore, 

 no provision was made for geographical races, which are, in fact, 

 incipient species : and this provision was also overlooked when the 

 important rules of the British Association were framed, in 1842. 

 Even in the last revised edition of these rules (1878), this great 

 desideratum is completely ignored. ' Were all species perfectly stable, 

 a purely binomial system would of course suffice ; but the more 

 recent developments of zoological research reveal the fact that com- 

 paratively few species are what may be termed completely isolated, 

 a ver}' large proportion being still united by a series of incompletely 

 differentiated individuals, even, in many cases, where the degree of 

 divergence in separate geographical areas is greater than between 

 many where intergradation is unknown and extremely improbable. 

 It is therefore clear, that the only true " species," or forms which may 

 be properly designated by a strictly binomial combination, are those 

 which are isolated through the extinction of intermediate specimens, 

 or the complete differentiation of the several offshoots from the 

 parent stock. And it is equally obvious that this distinction be- 

 tween real and incipient species should be practically recognized 

 by a suitable amendment of the rules of nomenclature. 



