In studying the birds of the West, one should note that there are western subspecies and varieties, which differ in some respects, though not materially, from their eastern cousins; for instance, the western robin, the western chipping sparrow, the western lark sparrow, and the western nighthawk. Besides, intermediate forms are to be met with and classified, the eastern types shading off in a very interesting process into the western. It would be impossible for any one but a systematist with the birds in hand to determine where the intermediate forms become either typical easterners or typical westerners. Most interesting of all to the rambler on avian lore intent is the fact that there are many species and genera that are peculiar to the West, and therefore new to him, keeping him constantly on the _qui vive_. In Colorado you will look in vain for the common blue jay, so abundant in all parts of the East; but you will be more than compensated by the presence of seven other species of the jay household. The woodpeckers of the West (with one exception) are different from those of the East, and so are the flycatchers, the grosbeaks, the orioles, the tanagers, the humming-birds, and many of the sparrows. Instead of the purple and bronzed grackles (the latter are sometimes seen on the plains of Colorado, but are not common), the Rockies boast of Brewer's blackbird, whose habits are not as prosaic as his name would indicate. "Jim Crow" shuns the mountains for reasons satisfactory to himself; not so the magpie, the raven, and that mischief-maker, Clark's nutcracker. All of which keeps the bird-lover from the East in an ecstasy of surprises until he has become accustomed to his changed environment. One cannot help falling into the speculative mood in view of the sharp contrasts between the birds of the East and those of the West. Why does the hardy and almost ubiquitous blue jay studiously avoid the western plains and mountains? Why do not the magpie and the long-crested jay come east? What is there that prevents the indigo-bird from taking up residence in Colorado, where his pretty western cousin, the lazuli finch, finds himself so much at home? Why is the yellow-shafted flicker of the East replaced in the West by the red-shafted flicker? These questions are more easily asked than answered. From the writer's present home in eastern Kansas it is only six hundred miles to the foot of the Rockies; yet the avi-fauna of eastern Kansas is much more like that of the Eastern and New England States than that of the Colorado region.