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Show APPENDIX NN. 1307 12. Dendroica audubonii. 13. Dendroica olivacea. 14. Dendroica graciw. 15. Geothlypis macgilUvrayi. 16. Setophaga picta. 17. Cardellina rubr\ frons. Helminthophaga lucice, Virginia, and Dendroica gracice, are the only ones belonging ex" clusively to this region. Of Dendroica occidentalism townsendii, and nigrescens, the two f rst come more properly within the Pacific province, as they breed about the Columbia River and Northern Sierras, and only find their way to the Rocky Mountairs during the fall migrations, and then to the southern portions of the chain. Dendroica nigrescent is equally an inhabitant of both regions. Dendroica olivacea, Setophagapicta, and Cardellina rubrifrons only occur in onr territory in Southern Arizona. This portion of that Territory, as well as the corresponding part of New Mexico, faunally considered, belongs with and is indivisible from Northern Mexico. Leaving the middle region and approaching tho Pacific coast, we find that the number of warblers still diminishes, whether we consider the mountains proper, or the low coast regions. In this province we find no species which we< have not recognized in one or the other of the two provinces mentioned, though D. oocidentalis and D. townsendii are characteristic of this proviuce as summer residents. The following is the list: 1. Helminthophaga nificapilla. 2. Helminthophaga celata var. lutes cens. 3. Dendroica cestiva. 4. Dendroica occidental is. * 5. Dendroica townsendii, 6. Dendroica nigrescent. 7. Dendroica coronata f 8. Dendroica audubonii. 9. Geothlypis trichas. 10. Geothlypis macgilUvrayi. 11. Icteria virens. 12. Myiodioctes pusillus v& v. pileolatus. Two iostances are to be noted here where birds continuing unchanged as they pass from the eastern into the middle province, are in the Pacific region differentiated into varieties, namely, Htlminthophaga var. lutescens and Myiodioctes var. pileolata. The evident preponderance of the number of species of this group in the Eastern United States, taken in connection with the fact that so large a proportion of the forms that occur in the western half of the country are eastern species, but little changed, or, as in most instances, actually the sam*), and that so tew are peculiar to that region, seems strongly to favor the assumption that it was in the East that the family had its origin, and that few, perhaps none, of the group were indigenous to the West. A further consideration of the number of warblers inhabiting the more northern and eastern parts of North America, in comparison with those of the southern parts or Mexico and South America, seems to point to the conclusion that the original center of the family was actually in this ( the former) region, and that it radiated out from a comparatively circumscribed area, to become firmly established in and indigenous to the sections where it now flourishes. The Canadian and Hudsonian faunas, as restricted by Allen, receive a larger proportion of warblers in the breeding season than are to be found in any other region of North America of similar extent. In his geographical distribution of mammals, Wallace arrives at a similar conclusion respecting the Motacillidce, ( warblerB,) giving their probable origin as North- Temperate America. LIST OF BIRDS OBSERVED NEAR CARSON CITY, NEV., FROM AUGUST 25 TO SEPTEMBER 16, AND FROM NOVEMBER 10 TO NOVEMBER 20, 1870, WITH NOTES. TURDIOE. 1. Tardus migratorius, L., var. propinquus, R.- Nevada Robin. Under the above name Mr. Ridgway has recently described a western variety of the robin, and has indicated certain differences that obtain in the species as it occurs from the eastern base of the Rocky Mountains westward, as compared with examples of the bird from the region east of the Missouri Plains. The specimens we have seen from Nevada correspond well with his diagnosis of the above bird, and, while we cannot consider the forms in question as illustrating " two |