To! BIRDS [DISTRIBUTION, as h possible, be liven. -Its extent both southward and lifornian northward is somewhat indefinite. The avifauna of Cape vince. s ;m Lucas, at the extremity of the peninsula of Old or Lower California, is said to be thoroughly that of the " Middle " province, but whether the whole of that pro montory is to be reckoned as belonging thereto, or only its eastern border, is not known. It appears, however, that some of the most characteristic forms of the Middle province find their way to the Pacific coast through a break in the mountains opposite to San Diego, and it is to be remarked that the difference between the species of birds found at Cape San Lucas (of which about a score are absolutely peculiar) and of Mazatlan, though separated only by the breadth of the Gulf of California, is very great. Northward the boundary of the Californian province probably runs along the Sierra Nevada and the Cascade Mountains before named, so that its extent is contracted to a mere strip along the coast, while still further to the north, in British Columbia, no precise details of its limits have as yet reached this country. But it would seem that in Alaska, as will presently be stated at greater length, an avifauna presenting many very different characters from any found elsewhere in America is reached, for here we encounter a number of genuine Palsearctic forms. ndian But these are not all the zoological provinces into which vince. this part of North America can be separated. A. fourth, of especially Arctic type, occupies the northern portion of the continent, and gradually melts away into the rest, extend ing far to the southward along the highest ranges, even to Fort Burgwyn, in lat. 37 N., if not beyond. This province may be called the " Canadian," from the ancient colony of that name constituting so large a portion of it, but its limits must be confessed to be indefinite in a high degree. The eastern half, at least, of the British possessions in North America are herein included, and the province may be deemed to extend across Davis s Strait to Greenland. In noticing these provinces, the results of Professor Baird s researches have been, with little deviation, mainly adopted, but his enquiries have been largely supplemented by the more recent investigations of Mr J. A. Allen, who has admirably carried out the further subdivision of the Eastern, or, as it has been termed, the Alleghanian province, together with part of what has just been denominated the Canadian. Regarding the whole eastern half of the con tinent as one province, he recognises in it the existence of seven distinct ornithological faunas, namely, the Floridan, the Louisianian, the Carolinan, the Alleghanian, the Canadian, the Hudsonian, and the American-Arctic, comparing them also with the distribution therein of Mammals and Reptiles. 1 To describe more fully the boundaries of these faunas would be to enter on matters too special for our present purpose, and it must suffice to direct attention to this essay of Mr Allen s, which, like others of his, 2 though their titles may seem to indicate for them but a limited scope, has, in truth, a very general bearing.
- uliar The provinces above named (and naturally the districts
tnbu- which they comprise) appear to be characterized rather by the presence or absence of certain species of widely-spread genera than by the presence or absence of the genera themselves, and much less of families, but it seems expe dient to notice some of the chief exceptions to general distribution in the latter of these groups. First we have the peculiar family of Chamceidce, restricted so far as is known to the coast-district of California, where it is repre sented by a single genus and a single species ; and then 1 Bulletin of the Museum of Comparative Zoology at Harvard College, vol. li. pp. 387-407. 5 Memoirs of the Boston Society of Natural History, vol. i. pp. 448-526, and Bulletin of (lie Museum, of Comparative Zoijlogy, vol. iii. pp. 113-183. among families of greater range, the Coerelidce, already introduced to us as a Neotropical group, but in the Nearctic Region existing only in the case of the colony of a species of Certhiola before noticed ; the Aridce, nowadays almost limited to Western Louisiania, Arkansas, and Florida, but formerly known along the whole valley of the Mississippi to the verge of the Great Lakes, and even occasionally penetrating to Pennsylvania and the State of New York ; the Cathartidce, of which one genus (Pseudoyryphus), having for its sole species one of the largest birds of flight, the Californian Vulture (P. calif omianus), is confined to the Pacific coast from a little north of the Columbia River to the Colorado, extending eastward to the Sierra Nevada, while of another genus (Catkartes) one species ranges from the Strait of Magellan to the Saskatchewan, but a second hardly strays further northward than North Carolina, and does not occur on the Pacific coast of the United States ; the Turkeys (Mdeagrida} found only to the eastward of the Rocky Mountains, and now extinct in most of the settled districts of Pennsylvania, New England, and Canada; the Wood-Ibises (Tantalidai), belonging to the southern country from the Colorado eastward, and so far to the north as the State of Ohio and the Carolinas; the Spoonbills (Plataleidce), with apparently much the same range as the last, but more limited towards the north, being of only accidental occurrence on the Lower Mississippi and in the Carolines ; the Courlans (Aramidce), frequenting in this region only the shores of the Gulf of Mexico and the coast of Florida ; the Flamingoes (Phcenicopteridce)^ with haunts nearly as much confined, though occasionally reaching South Carolina; the Pelicans (Pelecanidoi), having one species abundant in the Western and only by chance occurring in the Middle and Eastern states, while a second is of strictly marine habit, and is found on the coast of California, and in the Gulf of Mexico and the shoals of Florida. The single representative of the Darters (Plotidce) in summer reaches North Carolina and Illinois, but that of the Frigate-birds (Frcgatidce) is confined to the shores of the great Gulf, while that of the Tropic-birds (Phaetontidce) not only haunts the same waters but also finds a nursery in the Bermudas ; the species of Divers (Colymbidtv) breed only in the north Halifax, in lat. 45 N., being perhaps their most southern limit of reproduction ; while, finally; the Auks (Alcidae), Sea-birds of northern range, exhibit a most remarkable development of genera, species, and individuals on the rocky cliffs and islets which rise from the North Pacific. Reference has already been made to the peculiarity of Alas! the avifauna of Alaska Russian America, as it was for merly called, and its character needs brief notice. The list of Birds observed in this territory, as given by Messrs Dall and Bannister, 3 seems after due revision to number 210 species. Of these 96 are Land-birds, belonging to 63 genera, whereof 20 at the outside are peculiarly American, while of the remaining 43, which are common to the Nearctic and Palsearctic Regions, 3 are found nowhere else in the New World but in Alaska, and their occurrence there does not preclude us from setting them down as being emphatically Palaearctic forms. Two of them are actually represented by species common throughout the greater part of Asia and Europe, as is the case with Budytes flavus, a Yellow Wagtail, and Phylloscopus borealis, a Willow- Wren, while the third is a peculiar species of Bullfinch, Pyrrhula cassini. Of the whole 96 species of Land-birds, 23, or nearly one-fourth, are common to the two Regions. The Water-birds, amounting to 115 species, are referable to 63 genera, of which only 4 (all belonging to Scolopacidce) are 3 Transactions of the Chicago Academy of Scici 310.
nccs, vol. i. pp. 207-
