It is a very curious fact, in the history of this genus, that a variety of Regulus calendula, or a very closely allied species, should be among the few resident birds which constitute the isolated fauna of the island of Guadeloupe, 200 miles south of San Diego, Cal.

PARUS ATRICAPILLUS SEPTENTRIONALIS, Harris.

LONG-TAILED CHICKADEE.

An abundant resident of the region of the Upper Missouri, in all suitable situations; but neither this nor any other species of the genus was noticed in the Red River Valley. It is the characteristic form of the whole Rocky Mountain region from the Fur Countries into Mexico, where it is the only representative of the genus, excepting P. montanus. Detailed measurements of a series of specimens of this disputed form, for comparison with those of P. atricapillus, will be found in my work already quoted. These were carefully made in the flesh, at Fort Randall, during the winter of 1872-73. The average length was found to be 5.50 inches; the wing, 2.40 to 2.75; and the tail, 2.60 to 2.80.

A specimen procured at Chief Mountain Lake is preserved among the collections of the Commission.

Observed as far west as the confines of the Missouri Coteau. The westernmost specimens, as well as those from the immediate valley of the Red River, appear to be typical aedon. The Eastern form has also occasionally been met with in the Missouri region itself; though there the prevailing type is the var. parkmanni.

On the Red River, in June, the species was breeding very abundantly in the neighborhood of the fort and town of Pembina.

CISTOTHORUS STELLARIS, (Licht.) Cab.

SHORT-BILLED MARSH WREN.

The present is one of a few species of general distribution in the Eastern Province, which appears much more abundant along its line of migration in the Mississippi Valley than on the Atlantic coast. In the East, the species does not appear to have been observed beyond Southern New England. The present specimens, secured at Pembina in June, and later in the season along the Mouse River, are the northernmost on record, probably representing about the limit of its distribution in this quarter. The species has been observed westward to the Loup Fork of the Platte. I found the birds to be rather plentiful along the Red River, in low, oozy ground overgrown with scrub willows, and also in the reedy sloughs of the prairie. They were undoubtedly breeding here, though no nests were secured.

This species was not observed till we reached the Rocky Mountains, when a few were seen on marshy ground near Chief Mountain Lake. It is, however, of undoubted occurrence in suitable situations along the Line.

EREMOPHILA ALPESTRIS LEUCOLEMA, Coues.

WESTERN HORNED LARK.

One of the most interesting points in the history of the Horned Lark is its peculiar distribution during the breeding-season. Its breedingrange is in no way related to zones of latitude, nor yet is it determined by altitude, but by the topographical features of the country. It rarely, if ever, stops to breed along the Atlantic coast so far south as New England, where the surface of the country is not adapted to its peculiar wants. It is stated to occasionally nest in portions of Canada West; but it is not until we reach the valley of the uppermost Mississippi, in a broad sense, that we find the bird regularly breeding within the United States. I am informed by Mr. W. K. Lente, who accompanied the expedition during the season of 1873, that it nests in Wisconsin, near Racine, laying about the middle of April, even before the snow is off the ground.

From the Red River and corresponding longitude, west to the Rocky Mountains, it breeds in profusion, and during the greater part of the year it is, without exception, the most abundant, universally diffused, and characteristic species of the prairie avifauna. Numerous specimens were taken, not only along the parallel of 49°, but also on the Missouri and Milk Rivers, and the species accompanied our line of march into the mountains. The individuals bred in this dry and sterile region are usually lighter-colored than those of better-watered areas, and are those which I have designated by the term leucolama, in indication of a slight geographical differentiation.

The Horned Lark is one of the few species which, in this latitude, usually rear at least two broods each season,—a fact which in part accounts for the preponderance of individuals over those of the species with which they are associated. I have already adverted to the extremely early nesting-time which has been ascertained, and have only to add that the period of reproduction is protracted through July. I have observed young birds on the wing in June, and found fresh eggs in the nest during the latter half of July. In fact, all through the summer months the troops of Larks everywhere to be seen consist of old birds mixed with the young in all stages of growth. The great flocks, however, are not usually made up until the end of the summer, when all the young are full-grown, and the parents, having concluded the business of rearing their young, have changed their plumage. The young of the first brood soon lose the peculiar speckled plumage with which they are at first covered; the later ones change about the time the feathers of the old birds are being renewed. The agreeable warbling song is scarcely to be heard after June.

While it is not probable that any of these birds endure the full rigors of winter in the exposed country of this latitude, I am unable to say when they retreat. They continue abundant until October, and probably only retreat before the severe storms of the following month, to return again in March, if not in February. It is brave and hardy, one of the few birds that weather the terrible storms that usually prevail in April in the Missouri region.

The nest of the Horned Lark may be stumbled upon anywhere on the open prairie. It is a slight affair,-merely a shallow depression in the ground, lined with a few dried grass-stems. The eggs are four or five in number, measuring nearly an inch in length by about three-fifths in breadth; they are very variable in contour. The color is well adapted to concealment in the gray-brown nest, being nearly the color of the withered materials upon which they rest, thickly and uniformly dotted with light brown. The eggs and young birds, like those of other small species nesting on the ground in this region, often become the prey of the foxes, badgers, and weasels, if not also of the gophers.

The Horned Lark is a sociable bird, not only highly gregarious with its own kind, but one that mixes indiscriminately with several other spe.

cies, as Sprague's Lark, the Savanna Sparrow, Baird's, Maccown's, and the Chestnut-collared Buntings, all of which are abundant birds of the same region.

In the general area surveyed by the Commission, the Titlark appears to be only a bird of passage, in spring and autumn. During the first season I accompanied the Survey, none were observed until September, when, with arrival of various other species from the north, they made their appearance in considerable numbers along the Mouse River. The following season, however, I found them in August about Chief Mountain Lake, and do not doubt that those then observed were bred in the immediate vicinity, as at that time the fall migration had not commenced. In the Eastern Province, the Pipit agrees closely with the Horned Lark in its distribution during the breeding-season; in the

West, however, the case is reversed, the altitudes at which it nestles being complementary to the latitude it elsewhere seeks for the same purpose. It nests abundantly in the Rocky Mountains, above timberline, along with the Ptarmigan, as first determined by Mr. J. A. Allen, and subsequently very fully set forth by Mr. T. M. Trippe, at pp. 231, 232, of the "Birds of the Northwest". Its general habits as observed in the West furnish no occasion for special comment.

This very interesting bird, which in this country represents the celebrated Skylark of Europe, was discovered by Audubon in 1843, during his trip to the Upper Missouri. His type specimen, secured at Fort Union, June 19, is still preserved in the National Museum, having been among the many rare or unique specimens presented by him many years ago to Professor Baird. For about twenty years, no other specimens were forthcoming, and little, if anything more, was heard of the bird until an English officer, Captain Blakiston, met with it in considerable numbers in the Saskatchewan region, and contributed an account of its habits, as observed by him, to the "Ibis", then, as now, one of the very few journals devoted to ornithology. One of his specimens, like Audubon's original, reached the Smithsonian Institution, and remained until recently the only duplicate known to exist in any American collection. During my connection with the Boundary Commission I passed the season of 1873 in the very centre of abundance of the species, and collected over fifty specimens, all of which reached Washington safely and in good condition. Many more could have been secured, but I considered this number sufficient, not only for my own study of the species, but for distribution among other ornithologists, and various public collections in this country and Europe. During the same summer, my friend J. A. Allen, who was similarly engaged in field-work south of me, in the Yellowstone region, in connection with an engineering expedition then in progress, also became familiar with the bird, collected many specimens, and had the good fortune to discover the nest and eggs. These latter, now in the National Museum, are the only specimens, so far as I know, which have come under the notice of naturalists since Audubon first discov