COMMON CREEPER. 513 



though it has evidently retreated southward as the cold in the Arctic 

 regions has increased. In Western Europe it appears to range to about 

 63° N. lat., in Eastern Europe to about lat. G0°. In Siberia it has not 

 been recorded from further north than lat. 57° ; whilst on the American 

 continent, where the severity of the Arctic climate is not tempered by a 

 gulf-stream, it does not range beyond lat. 50°. In the south it frequents 

 the pine- and cedar-forests of Algeria, and has once been recorded from 

 Tangiers. It is also found in Asia Minor, Transcaucasia, Turkestan, 

 Cashmere, North China, and Japan. In America it is found as far south 

 as Guatemala. With such a wide distribution considerable local variation 

 must be expected ; and consequently the Common Creeper has been divided 

 into several species, varying in colour. These variations, however, appear 

 to me climatic rather than geographical. The palest form appears to be 

 that found in Central Siberia. Examples from the Amoor are slightly 

 more rufous, but not quite so much so as examples from North China, 

 Japan, and Asia Minor, which appear to approach the eastern North- 

 American form. In western North America the Creepers are still more 

 rufous, and are undistinguishable from British and Central European 

 examples, the more rufous individuals of which are again scarcely distin- 

 guishable from the palest examples from Mexico and Cashmere, which 

 latter are tropical forms, much darker on the upper parts, much more 

 rufous on the rump, and somewhat darker on the flanks. Modern orni- 

 thologists, fettered by the binomial system, and biased by the notion of 

 geographical regions, are obliged to be alternately lumpers and splitters, 

 according to the hemisphere with which they have to deal, instead of simply 

 recording the facts of nature. In the present case the Old-world tropical 

 variety of the Common Creeper has been called Certhia nipalensis, and has 

 been separated from the New-world tropical variety, which has been called 

 Certhia mexicana, whilst the far more distinct semiaictic forms Certhia 

 familiaris and Certhia scaudulaca have been confounded together, because 

 they are both Palsearctic. The Mexican variety of the Common Creeper 

 may, however, be usually distinguished from the Himalayan variety by 

 having the grey of the underparts extending further on the breast. 



There are other local variations in the Common Creeper ; for example, 

 the Creepers of South Europe in the Pyrenees and the Alps are much 

 paler than those found in the valleys ; and in all parts of its distribution 

 small examples occur, generally having the hind claw somewhat shorter 

 than usual, which has given rise to the term C. brachydactxjla, which many 

 continental ornithologists consider a good species : these latter birds are 

 probably immature. In Turkestan and India there are two near allies of 

 the Common Creeper which appear to have become good species, although 

 each of them is divisible into two subspecies. C. himulayana from the 

 Himalayas, and its long-billed pale form C. tceniura from Turkestan, 



VOL. I. 2l 



