VOl 'l906' in ] J ENKINS > Variation in the Hairy Woodpecker. 169 



Dryobates villosus intermedins, ranging in the territory between 

 hyloscopus and jardini, is smaller than hyloscopus, larger than 

 jardini, and is also intermediate in smokiness of the underparts. 



Besides the eight subspecies mentioned, there are two island 

 forms that are not known to intergrade with the continental species. 



Dryobates picoideus 1 inhabits the Queen Charlotte islands off 

 British Columbia. It has the white stripe on the back barred or 

 spotted, and is entirely distinct from any other form. 



Dryobates maynardi includes two subspecies, D. m. maynardi 2 

 of the southern and D. m. piger 3 of the northern Bahama Islands. 

 In 'The Auk,' XXII, April, 1905, pp. 124-126, Mr. Allen has 

 shown that piger and maynardi intergrade, but it seems that 

 neither one intergrades with the mainland avduboni. (The 

 name Dryobates maynardi piger (Allen) is more nearly correct 

 than Dryobates villosus piger Allen, if we would fulfil the require- 

 ments of "the test of intergradation for subspecies." However, 

 having recognized the subspecies, it is to be admitted that the com- 

 bination is really of minor importance.) 



Viewing the Hairy Woodpeckers as a whole we see that there 

 are certain variations in the structure of the birds corresponding 

 to certain regions. Why these variations exist we cannot say with 

 certainty. It is probably through natural selection and the sur- 

 vival of those best fitted to escape from enemies or to obtain food 

 in the particular region that they inhabit, but why a profusely 

 spotted bird can get along better in certain localities than in 

 others, and a large bird can get along better in the north than 

 in the south is hard to say. 



Taking up the lines of variation separately we have first, the 

 Spotting: — 



It is plain that the spots on the inner webs and proximal ends of 

 the feathers are more persistent. So we might reason that the 

 western bird is more highly developed, as follows: that the spots 

 so common among the Woodpeckers were originally developed 

 for some good service, as for directive markings, etc. ; but to make 

 the bird less conspicuous while climbing up dark colored tree trunks, 

 the white on the outside of the closed wing was greatly reduced. 



1 Osgood, N. Am. Fauna No. 21, 1901, p. 44. 



2 Ridgway, Manual N. Am. Bds., p. 282 (1887; see Cory, Auk, 1886, p. 375). 

 8 Allen, Auk, XXII, 1905, p. 124. 



