114 BULLETIN OF THE 



greater intensity of color than at the northward was noticed, in accord- 

 ance with the law of the increase in intensity of color to the southward,* 

 which in several species was especially marked. The males of the 

 common indigo-bird ( Cyanospiza cyaned) were not only much more 

 than ordinarily lustrous, but the females shared the blue tint of the 

 males to an unusual degree. There was here found also a thick -billed 

 race of the cardinal (Cardinalis virginianus), which in the size and 

 form of the bill makes a decided approach to the thick-billed race of 

 this bird found in Lower California (C igneus auct.). The hairy 

 woodpecker begins to noticeably resemble the darker (Picks Harrisii) 

 race of the Rocky Mountains, and Colaptes auratus has quite commonly 

 a greater or less number of red feathers mixed with the black ones 

 forming the maxillary patches, thus clearly showing a marked ten- 

 dency to a differentiation towards the C. mexicanus of the western half 

 of the continent, at a point some six hundred miles east of the habitat of 

 that species. A well-marked variation is also noticeable in the Icterus 

 Baltimore, through the paler colors of the middle wing-coverts, which 

 in Middle Kansas become either pure white or are only faintly tinged 

 with pale yellowish, instead of being orange, as in the eastern form. 

 With this gradual change in the color of the coverts the white edgings 

 of the remiges become greatly broadened, as in the so-called Par us 

 septentrionalis, the latter being here less strongly marked in this respect 

 than further westward. The bill of the Icterus Baltimore is here slen- 

 derer and rather more decurved than in northern specimens. Pro- 

 fessor Baird has also recorded a specimen of Pipilo erythrophthahnus 

 from Fort Leavenworth, which " has a few white spots on the scapulars 

 only, the wing-coverts without them, exhibiting an approach to P. 

 arcticus" f and remarks that other western specimens have more than 

 the usual amount of white on the wings. The Fort Leavenworth speci- 

 men he regards as "probably a hybrid," between P. erythrophthalmus 

 and P. arcticus. While only one of our Fort Leavenworth specimens 

 thus approached P. arcticus, all resembled it in the enlarged hind claw, 

 and in a more than the usual amount of white on the wing.| 



* See Bull. Mus. Comp. ZooL, Vol. II, p. 233. 



t Birds of North America, p. 513. 



\ In respect to the claws, I find that in the Fipilos of this group there is a decided 

 enlargement of the claws to the southward, along the Atlantic coast, as well as in the 

 interior and on the Pacific coast, this enlargement reaching its maximum in Lower 

 California, in Pipilo megalonyx of this group. Florida specimens have larger claws — 



