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and is seen very commonly in the immediate vicinity of the river as far south, at least, as the Massachusetts line. Spoon-wood (Kalmia latifolia) and gray birch (Betula alba, var. populifolia) find their northern limit in this town at a point opposite Dummerston, Vt. South of Brattleboro, deer grass (Rhexia Virginica), false fox-glove (Gerardia flava) and at the mouth of the Ashuelot River in Hinsdale, N. H., Cornus paniculata and Alnus serrulata, are the principal additions before reaching Massachu

setts.

Beside these there are others, and they would probably make up a much larger list, which are probably never found at these northern limits growing at an altitude much above that of six hundred feet above the sea, but for which I have not been able to gather sufficient data to warrant making the same approximation.

I will mention the northern limit at which I have observed a few of them moon-seed (Menispermum Canadense), groundnut (Apios tuberosa), near Windsor, Vt.; Desmodium Canadense and Betula lenta at South Charlestown, N. H.; Prunus pumila, islands of the river near Quechee Falls in Plainfield, N. H.; Aster undulatus and water-plantain (Alisma Plantago) at Hanover; Viola sagittata and river beech (Carpinus Americana) at Haverhill, N. H. Calystegia sepium and Virginia creeper (Ampelopsis quinquefolia) occur as far north as Lancaster, N. H., but are probably Alleghanian species which have been hardy enough to extend thus far northwards in spite of the increased severity of the climate.

The coltsfoot (Tussilago Farfara), if an introduced plant, must have entered the Connecticut Valley by the way of Canada, and seems to find the soil and climate north of Dalton best adapted for its growth, being abundant on the high clay banks of the river and along the mountain tributaries, but occurring much more rarely below the altitude of six hundred feet.

The distribution of the different species of grapes belonging to this valley is somewhat interesting. Vitis cordifolia is the hardiest, extending as far north as the foot of Fifteen Miles Falls. The summer grape (Vitis æstivalis) has not established itself north of Bellows Falls. I have been unable to find that the foxgrape (Vitis Labrusca) is indigenous anywhere in this valley, north of Massachusetts; but it is common along Miller's River and its tributaries in that State, which would indicate that the northern point for this species is near its mouth.

A few species seem to have found the valley of the Ashuelot River better suited to their growth than the main river valley north of its mouth. We find the flowering dogwood (Cornus florida) at Hinsdale; Sagina procumbens, Cyperus filiculmis, and C. strigosus, common along the plains of Keene and Swansey; and in the swamps, Symplocarpus fœtidus, which attains a greater range than the others, having established itself in the bogs around the base of Monadnock.

In the Merrimack Valley and that part of New Hampshire east of it, Canadian plants are fewer in numbers, both of species and individuals, than in the same latitude of the Connecticut Valley. Also, owing probably to the greater distance from the high lands, and to being much nearer the ocean, we find many Alleghanian species which do not extend in the Connecticut Valley farther north than Central Massachusetts.

It is somewhat surprising to any one familiar with that part of New Hampshire occupied by the Connecticut and its tributaries, to find the district belonging to the Merrimack the richest floral region in the State, and this, too, notwithstanding that the soil is not nearly so fertile. But it only proves that the warmer temperature of Eastern New Hampshire is more than enough to compensate for any decrease in the number of species that might be brought about by a less fertile soil.

We here find that the species traced throughout the former region do not seem to arrange themselves in groups with wide intervals between them, nor do their limits always appear in the same order.

In the Pemigewasset valley the frost grape first appears near the mouth of the East Branch, but nothing is seen of sheep laurel (Kalmia angustifolia) and sweet-fern (Comptonia asplenifolia) until near Plymouth, twenty miles further south. Arbor vitæ (Thuja occidentalis) stops near the south line of Thornton, but its companion, Alnus viridis, continues somewhat common to where the junction of the Pemigewasset and Winnipesaukee rivers forms the Merrimack.

A short distance south of the mouth of the East Branch, near the south line of Campton, Pinus rigida, P. resinosa, and gray birch (Betula alba, var. populifolia), make their appearance, and the white oak (Quercus alba) before reaching Plymouth, but the chestnut is wholly wanting north of the mouth of Smith's River, a short distance below Bristol. Rhus copallina is abundant at Livermore's Falls, just north of Plymouth. Vaccinium vacillans

and Quercus ilicifolia have their northern limit at Boscawen, shell-bark hickory and huckleberry at the mouth of Winnipesaukee River, while buttonwood (Platanus occidentalis) is found along the banks of the Pemigewasset, nearly to Plymouth. Mountain laurel (Kalmia latifolia) extends north to Concord, and Asclepias tuberosa to Thornton's Ferry.

From Concord to Nashua, we find near the river the following species, which appear to be wanting in that part of the Connecticut Valley belonging to New Hampshire. Commencing at Concord we find red ash (Fraxinus pubescens), Clethra alnifolia, Scirpus sylvatica, and S. microcarpa. The sand hills at Hooksett are sprinkled with bird's-foot violet (Viola pedata). The plains opposite Amoskeag Falls support a dwarf oak (Quercus prinus, var. humilis), which continues to be abundant, forming along with Quercus ilicifolia the shrub-oak thickets so common to these sand plains. Here, also, the bear-berry (Arctostaphylos Uva-ursi), generally supposed to be a highland species, occurs in greater abundance than elsewhere in the State.

Some of the swamps in this vicinity are filled with Cupressus thyoides, the white cedar of all the coast towns of Massachusetts. Another tree common to the borders of these cedar swamps in the same localities, the swamp white oak (Quercus bicolor), appears at the mouth of the Souhegan River, and Salix tristis is the common willow of the dry plains in this vicinity. Near Nashua we have Aster patens, blazing star (Liatris scariosa), sea sandreed (Calamagrostis arenaria), prickly ash (Zanthoxylum Americanum), and in the adjoining town of Hudson the climbing fern (Lygodium palmatum). Struthiopteris Germanica, the ostrich fern, seems to be properly a Canadian species, not occurring south of Concord in this valley.

We find the water-shed between the Merrimack and Connecticut to have a predominant Canadian flora as far south as the latitude of Bellows Falls. Below this point the Alleghanian plants have found the temperature such as to allow them to attain to higher elevations, and to mingle with the northern types, and the strictly Canadian forest is limited to the cold swamps and summits of the highest hills.

From the data which I have been able to collect concerning Vermont, it appears that the greater portion of the State is occupied by the Canadian flora, and that the area occupied by white and black spruce and arbor vitæ is considerably greater than that occupied by the same trees in New Hampshire; the Alleghanian

area, aside from that of the Connecticut Valley, being included in a narrow belt extending the entire length of the State west of the Green Mountains. Throughout its extent white oak, bitter hickory, pitch and red pine, sweet-fern and frost grape are common, mingling at the northern end of Lake Champlain with the Canadian arbor vitæ and white spruce. The chestnut, buttonwood and mountain laurel probably do not exist much north of Burlington.

The following species which are to be met with in New York and further westward do not appear to be found east of the Connecticut Valley, and most of them are confined to the immediate vicinity of the river: Carya amara, Celtis occidentalis, Populus monilifera, Salix longifolia, and Salix livida, var. occidentalis; the last one of these having the widest distribution being found throughout the entire valley, but apparently not passing over the water-shed into the Merrimack district. The hairy-leaved white violet (Viola renifolia, Gray; n. sp.) is to be met with between the mouth of the Passumpsic and Plainfield, N. H.

The following may be called rare, having but a single locality for each: Lobelia Kalmii, ledges at the foot of Fifteen Miles Falls; Cypripedium pubescens, at Hanover; Arabis Drummondii, on an island in the river just south of White River Junction ; and Astragalus Robbinsii, rocks at Quechee Falls, Plainfield, N. H.

IN

THE SUESSONIAN FAUNA IN NORTH AMERICA.

BY PROF. E. D. COPE.

a paper read before the National Academy of Sciences at the spring session of 1876 in Washington, the writer announced the identification of the Wahsatch Eocene formation of New Mexico with the Suessonian or Lower Eocene of France and England. The beds, which were explored while connected with the United States Geographical and Geological Survey, west of the one hundredth meridian, in charge of Lieut. G. M. Wheeler, in 1874, were found to contain the remains of a fauna, almost identical with that of the European beds in question. This was thought to be an important accession to American geology, as furnishing a basis for an estimation of the relative ages of the ormations immediately above and below the Wahsatch horizon. The parallelism of the fauna includes the genera of reptiles, birds,

and mammals, and among the latter, of the types both of carnivorous and of hoofed quadrupeds. Gar-fishes (Lepidosteus) appear in both countries, and the predominant mammalian genera of both are Coryphodon and Hyracotherium. Gigantic birds inhabited the land; in New Mexico they belonged to the genus Diatryma, and in France to Gastornis. The New Mexican genus Ambloctonus represents the carnivorous Palæonyetis gigantea of the lignites of Soissons. The only marked difference between the faunas which the then state of discovery disclosed is the existence of the order Taeniodonta in New Mexico, a type presenting characters of the Edentata, Rodentia, and Creodonta, which had not yet been found elsewhere.1

The characters of the mammalian fauna are very peculiar, displaying inferiority in many respects. Thus, among the flesheaters the brain of the Oxyana is of reduced size, the hemispheres being especially small, while the olfactory lobes are very large and uncovered; and other Creodont genera present the same character. According to Gervais the genus Arctocyon, from the Suessonian, presents the same type of brain. The hoofed type, Coryphodon, shows a similar inferiority in the constitution of the brain.

So far as these observations have gone, they coincide with those made eight years ago by Professor Edouard Lartet of Paris. He states that it is the result of a number of investigations undertaken in different horizons of the Tertiary strata, that the more we follow Mammalia into the antiquity of geological time, the greater is the reduction of the volume of the brain in comparison with the size of the head and the total dimensions of the body. Cuvier observed the form of the brain of the Anoplotherium in a cast of marl which was consolidated within the cavity of a skull of this animal, found in the gypsum of Montmartre. He says "it has little volume, and is flattened horizontally; the hemispheres do not present convolutions, but we find only a shallow longitudinal impression on each. All the laws of analogy authorize us to conclude that our animal was greatly deficient in intelligence." In fact the skull of the Anoplotherium is six times as long as the cast of its cerebral hemispheres, and this animal, which in dimensions Cuvier compared to a medium-sized ass, had a brain smaller than that of the existing roebuck.

1 See American Naturalist, 1876, p. 379.

2 Comptes rendus, June, 1868.

8 Ossements fossiles, iii., p. 44.

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