ON SUBSPECIFIC FOEMS. 



65 



nomenclature, but they were the first to use it in a strictly scientific manner. Schlegel, 

 in his ' Revue Critique des Oiseaux d'Europe,' made use of many trinomial names of birds. 

 On the very first page we find Falco candicans distinguished from Falco candicans islandicus. 

 The same idea may be traced up to Linnaeus, who distinguishes, in his ' Systema Naturae ' 

 (on page 125 of the 1st volume of the 12th edition), between Falco fulvus and Falco 

 fulvus (5. canadensis ; and down to Sharpe, who discriminates, in his ' Catalogue of Birds 

 in the British Museum ' (on page 6 of the 1st volume), between Gyps fulvus and sub- 

 species a. Gyps hispaniolensis. But none of these writers seem to have had any definite idea 

 of what they meant by a subspecies, they appear to use the term in an absolutely arbitrary 

 manner ; and we may safely say that they did not use it in the Darwinian sense of an 

 imperfectly differentiated species, which was still fertile with the parent form, and was 

 consequently connected with it by a potentially infinite series of intermediate forms. The 

 fact of the existence of species which consist of two or more typical forms which are 

 connected together by an unbroken series of intermediate forms between the geographically 

 separated extremes — for example, the fact that such apparently distinct species as Sitta 

 europeea and Sitta ccesia are thus connected, and are consequently only subspecifically 

 distinct — is the most important ornithological fact which has been discovered during the last 

 half-century. It is a fact which has been clearly recognized by American ornithologists, 

 and its tardy or doubtful recognition by British writers on birds is one of those psycho- 

 logical puzzles that are very difficult to believe, much less to explain. Some ornithologists 

 are apparently so obtuse that they are unable to understand the problem ; others are 

 prepared to admit the truth of the theory of Evolution as an abstract proposition, but are 

 prevented by an overruling hereditary conservatism from practically applying it to ornitho- 

 logy ; whilst a third class are unable to reconcile the facts of Evolution with their theories 

 of the origin of species, and, consequently, are afraid to acknowledge any truth which 

 appears to be inconsistent with their inherited superstitions. 



It is, however, only fair to remember that much allowance must be made for the 

 narrow, because insular, views of British ornithologists. The collections at Washington 

 contain magnificent series of Nearctic birds from the Atlantic to the Pacific ; whereas the 

 British-Museum collection, in spite of its wealth of Oriental species, is very poor in Palse- 

 arctic series. Ten years ago it scarcely possessed a workable series of any Palsearctic 

 species, though a few of the localities between Western Europe and North-eastern Asia are 

 now represented in some of the commoner species. 



Vague use 

 of trino- 

 mials. 



Conservative 

 views of 

 British orni- 

 thologists. 



