PICUS VILLOSUS, HAIRY WOODPECKER. 281 



Bix) on the primaries, and none on the inner secondaries and wing-coverts. The change 

 Legins ill birds from the eastern slopes of the Rocky Mountains, and is etfected by im- 

 perceptible degrees. Laying a few scores of s)iecimens side by side, in linear series 

 representing the change in longitmle, one may see the spots disappear one by one, or 

 by jiairs, proving the complete intergradaticm of the two iornis. This has been known 

 to several ornithologists for some years, and hints to this effect have repeatedly been 

 given ; but, so far as I am aware, it was not formally recognized, by reduction of harri-iii 

 to a variety, until this was done simultaneously by Mr. Allen and myself. 



We will next observe that the original of Ficns harrisii, from the Columbia River, 

 has the under parts of a i^eculiar smoky-gray tinge, with also more or less evident thin 

 black stripes along the sides. This appears chiefly in specimens from Oregon and 

 Washington Territories, and I think is something more than mechanical soiling of the 

 feathers with carbonaceous matter from the trees, although this agent undoubtedly 

 sometimes effects a like result. All my New Mexican arid Arizonian specimens are as 

 pure white below as in the eastern variety, and usually lack all traces of stripes along 

 the sides. 



Resting upon these facts respecting the distinctions between the eastern and western 

 form, we will take up tlie remarkable variution in size that both exhildt in a perfectly 

 parallel manner. Specimens of typical villosus occur ranging from 8 to 11 inches long ; 

 and this difference is found to depend upon latitude, size increasing pari pasHu with 

 heightening of latitude, by insensible degrees. But there is nothing exceptional 

 about this; on the contrary, it is merely a strong illustration of the prevailing rule 

 with widely-distributed birds, the individuals of which are stationary or nearly so. 

 With the maximum size of the northern birds there is associated an increase of white- 

 ness, also in conformity with a general rule. These two particulars, size and hoariness, 

 give the bird a peculiar aspect, so readily distinguishable that the Picus " lencomelas" 

 or "canadcnsifi" has passed for a species with many writers. But I see no necessity of 

 recognizing it by even varietal name; if we did, we should also, to be consistent, sep- 

 arate the Hylotomus pilealus into races founded on size, the variation being fully as 

 great in this case. The smaller size of the South Atlantic and Gulf States' villosus is 

 recognizable, on an average, but is not so strongly marked; in coloration they are pre- 

 cisely the same as the ordinary bird of the Middle States. 



In the West, the boreal extension of var. harriNii is cut off by the topography of that 

 region, the westward trend of the mountains bringing the eastern zoological province 

 to the very Pacific, and giving us var. viUosus instead of harrisii. Consequently, typical 

 var. harrisii is itself the largest form. It about equals ordinary villosus of the Middle 

 States. The New Mexican and Southern Califoruian specimens are slightly smaller 

 than those of Washington Territory, but not notably so, the chief distinction being 

 the color of the under parts, as already noted {hijloscoims, Vabauis). But the Mexican 

 extension of tlie species, as well as I can judge by descriptions, is strongly marked by 

 its, small size, being quite as much under the average as F. " leuco7iielus" in over the 

 average. This is the P. jardinei of authors. The parallelism is thus seen to be com- 

 plete; in the east, a series with a marked northern maximum of size and less con- 

 spicuous minimum ; in the west, a marked southern minimum and less conspicuous 

 northern maximum ; in both cases, the variation directly and precisely according to 

 latitude; while the intergradation of the two according to longitude is perfect. 



It is too late to say much about the various nominal species establislied upon con- 

 ditions of immaturity; they have already been satisfactovily disposed of. But, 

 although so admirable and long-exporienced a tield-iiaturalist as Audubon miglit well 

 be excused for proposing harrisii and tjairducri, at a time when climatic variation had 

 no [dace in the conceptions of naturalists, it is incomprehensible that, after years of 

 study in the field, and shooting perhaps hundreds of Hairy Woodpeckers, he should 

 never have found out that the young males iiave more or less of the vertex red or yel- 

 low, instead of an occipital crescent of scarlet. Tliis crown-patch is sometimes per- 

 fectly sfpiare, and bright yellow, almost exactly as in I'icoidcs ; but it is oftener dif- 

 fuse, of a bion/.y or coppery hue, mixed with wh^te, &.c. I'. ^^ phiUipsii" is the young 

 of the northern race; /'. " ?(i«r//)(«''' may l)e so too, lieingfiom Canada, luit the ascribecl 

 dimensions (" length, 9^") are those of ordinary rillosus, to which it may be as well to 

 relegate it. " Scptcutrioualis" and ^^ ruhricapillus" of Nuttall are the same as "j)hil- 

 lipsii" and '' 7uartiua\" respectively. ^^ J'ivus auduhoiii" is one of the curiosities of 

 ornithological literature, inasmuch as Swainson and Trudeau, without the slightest 

 reference to each otlier, each proposed the same name for the same bird in the same 

 plumage, and not a valid species <'itlier. 



This species moults the (luills and tail-feathers very tardily ; they Jiersist with de- 

 creasing vitality, until Just Iji-fore tliey (hop they are often found faded, toward their 

 ends at least, into brownish-fc/ij/c. 



This condition has crept into some of the itublished plates. Another individual 

 peculiarity is, that the occipital scarlet band of the male is often discontinuous behind, 

 being thus resolved into two supra-auricular spots, almost exactly as in I'icus qucrulus. 

 This may have induced Ciiay to put^'«/(/(Ht( alongside /'. borcalis in the subgenus i'/irt/i- 



