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Reptilia, and as probably the ancestral group from which the latter were derived. This approximation is seen in the scapular arch and humerus, which nearly resemble those of the Monotremata, especially Echidna; and in the pelvic arch, which Owen has shown in the Anomodontia to resemble that of the Mammals, and as Prof. Cope pointed out, especially that of Echidna. The tarsus is also more mammalian than in any other division of reptiles. In the genus Dimetrodon the coracoid is smaller than the epicoracoid, as in Monotremes. The pubis has the foramen for the internal femoral artery.

The discovery of the Pelycosauria established the important fact that the first land Vertebrata possessed a chorda dorsalis.

A species of Dimetrodon was described under the name of D. cruciger. It is characterized by the enormous length of the neural spines of the lumbar vertebræ, which form the dorsal fin seen in other species of the genus. They are found in masses adhering together like sticks or branches of bushes. In this species the spine sends off, a short distance above the neural canal, a pair of opposite short branches, forming a cross. At various more elevated positions there are given off tuberosities which alternate. with each other. They form on several consecutive spines oblique rows. The spines are broadly oval in section, the long axis antero-posterior, and have a shallow groove on both the anterior and posterior aspects. The centra are elongate as compared with their other diameters, and are much compressed between the articular extremities, leaving a strong inferior median obtuse rib. Articular faces of zygapophyses oblique. Diapophyses short and robust, with large costal faces, and standing below the prezygapophyses.

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DISCOVERY OF RECENT GLACIERS IN WYOMING.-It was not known until curing the past season that genuine glaciers existed within. the limits of the United States, east of the Pacific coast, but last summer as two of the divisions of the Geological Survey under my charge were exploring the Wind River mountains in Wyoming Territory, we found living glaciers on the east side of the range. On the east base of the Wind River peak, which is at the south end of the range, there is a mass of snow and ice, 900 yards long and

500 wide, with all the elements of a true glacier. On the east base of Fremont's peak, which is over 14.000 feet high, we discovered two glaciers, one of which covers an area of one and onefourth square miles, and the other three-fourths of a square mile. They were marked by enormous crevasses; also with lateral and terminal moraines. We called them Upper and Lower Fremont glaciers. These would appear to be only insignificant remnants of the vast glaciers that must have covered these mountains during the true glacial period. On the west side of the range, the moraines and glaciated rocks are found on a vast scale. On the west side of the range, a glacier must formerly have existed, eighty miles long and twelve wide, with the arms extending up the gorges of the streams to the very water divide. These glaciers will be more fully described in the 12th Annual Report of the U. S. Geological Survey.-F. V. Hayden.

WASATCH GROUP.-Along the east side of the Wind River mountains and filling up the Upper Wind River valley, is a great thickness of modern Tertiary strata that has been weathered into very remarkable forms, and which are known in the West as "Bad Lands." The strata are most beautifully variegated with various shades of pink or brick-red color, so that they sometimes remind one of the Jura-Trias red beds. This formation was described by me in 1859, in detail, and named the Wind Kiver group. It covers a broad area in this region, extending from the source of Wind river to the Sweet Water mountains, south more than one hundred miles, and west an average width of one to five miles. The aggregate thickness of this group cannot be less than 5,000 feet. On the west side of the Wind River mountain, no formations older than the Wasatch group are found. This group rests, doubtless, on the Archæan nucleus, inclining at the base five to ten degrees. All the older sedimentary rocks have been entirely swept away from the granites for a distance of one hundred miles, while on the opposite or east side all the corresponding strata are visible from the Silurian to the Cretaceous; the Wasatch beds cover a large part of the Green River Valley, especially about its sources.

I am convinced, also, that a group of strata which I named in 1869, Gallisteo Sand group, in the valley of Gallisteo creek, a branch of the Rio Grande, is also the equivalent of the Wasatch group, though both Wind river and Gallisteo Sand group as names have the priority over Wasatch, yet the latter has been now so much used in the Reports on Western geology, that it will probably prevent the use of the former to any extent in the future. When the Northwest is more fully explored, it will probably be found that the Wasatch group covers a large area extending more or less from our north line far into New Mexico.-F. V. Hayden.

1 See Annual Report, page 177, reprint.

THE DEVONIAN AND SILURIAN FORMATIONS OF BRITTANY.-Dr. Chas. Barrois, of Lille, has published in the annals of the Geological Society of the North, for 1877, an account of his investigations into the geology of Brittany. He finds in the Devonian formation of that region, five well-defined horizons, some of which had been previously unknown in France. He discovered certain previously unsuspected relations between the formation, and that of the valley of the Lahn. At the Rode of Brest but three of these horizons are present, the second, third, and fifth. As regards the Silurian, Dr. Barrois finds the same horizons in Brittany that have been observed in other basins of the same formation. He, however, makes a number of rectifications of previous descriptions of the geology of Finistère.

THE GEOLOGY OF BELGIUM.-Much activity exists among the geologists of Belgium, and numerous articles have recently appeared, which advance the science in that country. The magnificent work of M. Van Beneden on the extinct Cetacea of the neighborhood of Antwerp, has reached the second part. M. Rutot has recently published an account of the fossils of the inferior Oligocene, and M. G. Vincent, the history of the Fauna of the Landenien inferieur. M. Rutot determines that the Nipadites and other fossil plants found in the neighborhood of Brussels, are derived from the Bruxellien, and not from the Lackenim as has been supposed. M. Lefèvre has discovered tortoises and Halitherium in the same region.

THE SOUTHERN BOUNDARY OF THE GLACIAL DRIFT.-In his Report as State Geologist of New Jersey, for 1877, Professor George H. Cook, presents some important facts relative to the southern limit of the glacial drift in that State. He finds it in a series of hills which cross the mouth of the Hudson river at the Narrows, and Staten Island Sound at Perth Amboy, which then extend northwards to near Morristown and Dover, and then westwards, crossing the Delaware river at Belvidere. These hills are composed of gravel, sand, boulders and stones commingled in a confused mass, and are identical in character with the material that fills the valleys to the north of them. The parent rock is in every case to the north, sometimes at a distance of twenty to thirty miles.

Professor Chamberlin, State Geologist of Wisconsin, presented to the Congress of Geologists recently held in Paris, a paper on the terminal moraine of the Great Lake District. Advance copies of the paper were printed in Paris. In this paper Professor Chamberlin describes an extensive belt of drift hills and ridges which traverse the quarternary deposits forming immense loops about the southern boundaries of the Great Lakes for a distance of 2000 miles in length, and a width of from one to thirty miles. Portions of this ridge had been observed by Lapham, Whittlesey, Andrews, and others. The material of the range consists of un

stratified débris of all formations adjacent northwards, with some stratification of the surface of an irregular kind. A peculiar feature of the range is the presence of large holes and sinks, some of which are full of water. From these holes the range is called the Kettle Moraine. Its distribution is alike regardless of the geological and topographical features of the country, excepting in its parallelism to the southern border of the Great Lakes. Professor Chamberlin regards it as a terminal moraine which marks a period in the history of the glaciers which are supposed to have once filled the depressions now occupied by the Great Lakes.

MIOCENE VERTEBRATA OF OREGON.-An examination of a collection of vertebrate fossils from the John Day river, Oregon, recently made by Prof. Cope, yielded the following species: Artiodactyla-Hypertragulus calcaratus Cope, Leptomeryx evansi Leidy, Eucrotaphus superbus Leidy, E. occidentalis Marsh, Merycocharus leidyanus Bettany, Hyopotamus guyotianus sp. nov., Thinohyus socialis Marsh, T. lentus Marsh, Elotherium imperator Leidy. Perissodactyla—Rhinocerus pacificus Leidy, Anchitherium equiceps sp, nov., A. brachylophum sp. nov., A. longicristis sp. nov., Daodon shoshonensis gen. et sp. nov. (allied to Chalicotherium). Carnivora-Canis gregarius Cope, C. lippincottianus Cope, C. cuspigerus sp. nov., C. geismarianus sp. nov., Temnocyon altigenis gen. et sp. nov., Machærodus strigidens sp. nov, M. brachyops sp. Rodentia-Meniscomys hippodus gen. et. sp. nov., M. multiplicatus sp. nov., Pleurolcus sulcifrons gen. et sp. nov., Entoptychus cavifrons gen. et sp. nov., E. planifrons sp. nov., E. crassiramis sp. nov., Steneofiber sp., Stencofiber gradatus sp. nov., Palæolagus haydeni Leidy.-Proceedings of the Amer. Philosophical Society.

nov.

GEOGRAPHY AND TRAVELS.1

THE AMAZON. In the September number of the NATURALIST mention was made of the survey of the Amazon and Madeira rivers, undertaken by the U. S. corvette Enterprise, Commander Selfridge. This vessel arrived at New York on the 25th of September last, and we learn from the New York Herald of the successful accomplishment of her mission. At Serpa, near the mouth of the Madeira they found the Amazon a mile in width and sixty feet deep. The Madeira is here about two miles wide, and its principal channel has a depth of from ninety to sixty feet, according to the season of the year. From near its mouth to the falls its banks are high and well marked. The steamer entered the Madeira on the 17th of June, and advanced without difficulty at the rate of twenty-five miles a day, stopping at night, until the 21st, when near the island of Araras the pilots reported rocks and shoals. Although careful investigation proved that no rocks were there, and five fathoms of water was found, it was not deemed advisable for the ship to cross, owing to the reports of 1 Edited by ELI IS II. YARNALL, Philadelphia.

the pilots and natives of the great and sudden changes in the rise and fall of the stream. The survey was, however, continued by the steam launch to San Antonio, a distance of about 325 miles, with the exception of the last thirty miles, which was, owing to an accident to the launch, made by Capt. Selfridge and Lieut. Perkins on board a Brazilian merchant steamer. Leaving the Enterprise on the 25th of June, the surveying party were again safe on board on the 20th of July. The results of their observations show that a navigable channel for ships drawing up to sixteen feet of water exists from the mouth of the Madeira to San

Antonio, a distance of 500 miles. This channel is passable during nine months of the year, but during the time of low water, namely, August, September and October, the river is so low that in many places not more than six or eight feet can be carried. The adjacent territory is very thinly populated. Large quantities of rubber are collected and shipped along the river, and also copaiba, sarsaparilla, copal and chouta, a black odoriferous gum used as a cement.

ARCTIC EXPLORATION. The schooner Florence, Capt. Tyson. which was fitted out and sent by Capt. Howgate to Cumberland Gulf to procure skins, dogs, sledges and other material for the use of his expedition, has returned home, and from a dispatch by Capt. Tyson to the New York Herald, we learn that he sailed from New London on the 2d of August, 1877, and reached the Gulf after a tedious voyage of forty-one days. Here they remained in Niantilic harbor, latitude 65° 10' north, longitude 67° 30' west, until October Ist, when they removed to Annatook harbor, at the head of the Gulf. There they passed the winter and spring. On the 19th of July they sailed for Disco island, taking with them fifteen Esquimaux, men, women and children, twenty-eight dogs, a fair quantity of skin clothing and a great many skins. Arriving at Disco on July 31st, they remained until August 22d, when no intelligence of the expedition being received, they returned, after a difficult passage through the ice off Cape Mercy, to the Gulf. After discharging the Esquimaux they started on their voyage home on the 2d of September. Messrs. Kumlin and Sherman, the scientific members of the party, were very successful in the performance of their duties. The former has secured a large number of specimens, and the latter, aided by two of the crew, took hourly observations during the winter. The season has been a bad one. Melville Bay has been entirely blockaded by the ice, no whalers having been able to penetrate it, and the Danish ships have been unable to reach the upper settlements.

RESULTS OF THE RECENT BRITISH ARCTIC EXPEDITION.-Sir George Nares has, in his "Narrative of a Voyage to the Polar Sea," recently published, given more fully his reasons why he

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