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as guides, apparently, and certainly as guards. Being at this time of the year very shy, they give notice of the approach of danger, and leading the flock, "Tell-tales," "Yellow-legs," "Solitaries" and "Teeter," fly in large circles, at a great height, and then resume their feeding near where they were previously to being flushed. During the breeding season, if frequently disturbed while feeding, they fly to their nests.

Both the "Tell-tale" and "Yellow-legs" have been found breeding in Mercer county, New Jersey. They seek some quiet nook along a small stream, and in the high grasses build quite a substantial nest, raising one brood that leaves the nest before being able to fly. At this time they are a dull mouse color, and when approached, squat so closely to the ground and remain so motionless, that. it is nearly impossible to detect them.

22. Solitary Sandpiper (Rhyacophilus solitarius). Although the numbers remaining in New Jersey during the summer vary very much, we have never failed to find them during June and July, and August brings them again plentifully from the North. They breed as regularly in the state as the Spizella socialis, if not as abundantly. While the number of isolated specimens we meet with is large enough to warrant the descriptive name solitarius, yet many are seen associated with the other Sandpipers, especially in May and early autumn.

23. Mallard (Anas boschas). 24. Green-winged Teal (Nettion Carolinensis). 25. Blue-winged Teal (Querquedula discors). 26. Buffle-headed Duck (Bucephala albeola).

There is generally in April or May a freshet in the Delaware River, and one that usually overflows the tract of meadow mentioned when speaking of the Snipe (Gallinago Wilsonii). During the prevalence of this high water the ducks usually make their appearance in large numbers, feeding over the meadows in loose flocks, the species being the Mallard (Anas boschas), Black-duck (Anas obscura), Sprigtail (Dafila acuta), the two Teal (Nettion Carolinensis and

Querquedula discors), Shoveller (Spatula clypeata), Widgeon (Mareca Americana), Wood Duck (Aix sponsa), Whistler (Bucephala Americana), and Buffle-head (Bucephala albeola).

After the waters have subsided they generally congregate at the river, and after a week or more, during which time many are killed, they have left. But not wholly so, as during the summer months, besides the beautiful Aix sponsa, which we always have, there are quite a number of Anas obscura always to be met with, and not unfrequently the four species we have mentioned above. Of the four species the Mallard is the most abundant, and the "Buffle-head" least. That they all breed in the state there can be no

question.

We conclude with the above, the selections from our notes, made in the field and at various times, on the peculiarities, if we may call them such, in the ornithology of New Jersey, with the thoughts they have suggested, believing they will be of interest to those especially giving attention to the subject of geographical distribution. Of the three hundred species of birds included in the ornithic fauna of New Jersey, of course there are many that are exceedingly rare in our territory. Among some species there have happened freaks of habit, unique instances so far as our experience goes, that though entertaining, are doubtfully of sufficient value to warrant their publication; but as apparently trivial occurrences have sometimes proved a help in the solution of difficult questions, we propose to give a plain narration of one or more such occurrences.

In January, 1869, an acquaintance in hunting over the Delaware (Trenton) meadows for hawks came to a lively spring in a hillside having a southern exposure. As he was about leaving it he flushed from grass still green and long, a pair of Virginia Rails (Rallus Virginianus), and fortunately killed them. They were both fat, showed no signs of having been previously wounded and thereby detained, and

flew as rapidly and with as much apparent vigor as in September. Farther search failed to discover others at the time. Two weeks later three others were killed, and in the first week of February, one more. These latter specimens were equally fat and vigorous. No similar circumstance has come under our notice.

Similar instances of the presence of the Night Heron (Nyctiardea Gardenii) have three times come under our notice. We have found these birds sitting on trees near springs, from whence the water flowed swiftly, and about which the grass remained quite fresh. Leaving them undisturbed, but watching them frequently, they were never seen to leave their perch. From the accumulation of droppings it was evident that the particular branch even, on which they were first seen, was that on which they had been resting for some time past. Only single specimens have been thus found, all male birds, and they have always been much emaciated. When forced to move they all proved able to fly, but returned to their accustomed place, after a circuitous flight of short duration. Were they too old to go South? Did they get any food? If so, what and where? On dissection the stomachs of these three specimens proved to be empty, but the uppermost droppings were fresh!

THE FORMER EXISTENCE OF LOCAL GLACIERS IN THE WHITE MOUNTAINS.*

BY PROFESSOR L. AGASSIZ.

TWENTY-THREE years ago, when I first visited the White Mountains, in the summer of 1847, I noticed unmistakable evidences of the former existence of local glaciers. They

* Read, in the absence of Professor Agassiz, by J. B. Perry, before the American Association for the Advancement of Science, Troy meeting, Aug., 1870.

were the more clear and impressive to me because I was then fresh from my investigations of the glaciers in Switzerland. And yet, beyond the mere statement of the fact that such glaciers once existed here, I have never published a detailed account of my observations, for the simple reason that I could not then find any limit or any definite relation between the northern drift and the phenomena indicative of local White Mountain glaciers; nor have I ever been able since to revisit the region for more careful examination. This year a prolonged stay among these hills has enabled me to study this difficult problem more closely, and I am now prepared to show that the drift, so-called, has the same general characteristics on the northern and southern side of the White Mountains. Whatever, therefore, may have been the number of its higher peaks which at any given time, during the glacial period, rose above the great ice sheet which then covered the country, this mountain range offered no obstacle to the southward movement and progress of the northern ice fields. To the north of the White Mountains as well as to the south, the northern drift consists of a paste more or less clayey or sandy, containing abraded fragments of a great variety of rocks, so impacted into the minutely comminuted materials as to indicate neither stratification nor arrangement or sorting, determined by the form, size or weight of these fragments. Large boulders and pebbles of all sizes are found in it throughout its thickness, and these coarser materials have evidently been ground together with the clay and sand under great pressure, beneath heavy masses of ice; for they have all the characteristic marks so unmistakable now to those who are familiar with glacial action: scratches, grooves, furrows, etc. These marks are rectilinear, but they cross each other at various angles, thus showing by the change in their direction that the fragments on which they occur, though held for a time in one and the same position while these straight lines were engraved upon their surface, nevertheless changed that position more or less frequently.

A few flatter fragments with more angular outlines show only one kind of scratches, having evidently been held for a longer time in the same position. This drift, however it may vary in its mineralogical components in different localities, exhibits everywhere the same characteristic treatment over the whole country, from the shores of the Atlantic to the Rocky Mountains and beyond. In the White Mountain region it has the same mineralogical character north and south of the range, and rests everywhere upon the well known roches moutonnées, in one word, upon the planed, grooved, polished and scratched surfaces of the rocks underlying it.

Observation has taught us that materials such as those described above, so combined, exhibiting the same characters in their surfaces and having the same diversity of composition and absence of all sorting or regular arrangement, occur now at the bottom of the great glaciers of our time, and nowhere else; being found between the ice and the rocks over which it moves,—the result in fact of the grinding action of advancing glaciers. On account of their unvarying position I have called these deposits "ground moraines," because they are always resting upon the rocky floor of the country, between it and the under surface of the ice. Our typical unaltered so-called northern drift is synonymous with the ground moraines of the present day, differing only in its greater extension. It is in fact a ground moraine spreading over the greatest part of the continent. All its characteristics, identical in every detail with those of the deposits underlying the present glaciers, show that it can only have been formed under a moving body of ice, held between it and the underlying mass of rock. The great ice sheet of the glacial period which fashioned the drift must therefore have been co-extensive with the distribution of the latter. It is very important to distinguish this drift from the moraines formed under other circumstances, and from the so-called erratics and perched blocks. Moraines, as commonly understood, that is, lateral and frontal mo

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