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the name Orarians (from ora, a coast), in reference to their universal coastwise distribution.

Various points of interest in regard to the several tribes were noted, and their comparative relations were shown by a table of twenty-four dialects, and a colored map showing their geographical distribution.

Prof. ALBERT S. BICKMORE read a paper “On the Distribution of Coal, Iron, Mercury, Tin, and the precious metals, in China. Prof. B. showed that coal occurs from place to place over the whole of China proper, and that iron is found in the north of China, especially in the Province of Shansi, where the ore is obtained from which the steel used in the manufacture of razors, kuives, etc., is made. Mercury, or “Water-silver” as the Chinese call it, occurs in Shansi in small quantities. Tin is reported from various localities. Petroleum was not only known but used in lamps more than 100 years ago. The Chinese name for it, “Oil of Stone," is identical with ours.

Prof. C. H. HITCHCOCK stated in his paper “On the Ammonoosuc Gold Fields,” that this area begins near Bellows' Falls, and extends into Canada, following the Merrimac river. It was at tirst referred to the Quebec group, but he thought the rocks distinct. The gold was found in 1864 in the rocks, by Mr. Henry Wurtz, at Lima, N. H. The rock is a black clay slate, with quartz veins containing iron pyrites, ankerite and galena.

Dr. C. C. PARRY in his paper “On the Rocky Mountain Alpine Region," stated that the wooded belt of coniferous trees begins by a somewhat scattering growth near their base at an average elevation of six thousand feet above the sea. This belt acquires its densest growth, and exhibits the greatest number of distinct species, at an elevation of between 7000 and 9000 feet, and terminates by an abrupt well-marked line, at an average height of 11,300 feet.

The limit of upright tree growth is marked with a singular abruptness. He explained this by supposing that the so called timber line marks the extreme point of minimum winter temperature, below which no exposed phenogamous vegetation can exist. All that survives above this point does so by submitting to a winter burial of snow, beneath which protecting cover it is enabled to maintain its torpid existence. The usual characters of alpine plants, here as elsewhere exhibited, consist in a dwarfed habit of growth, a late period of flowering, and early seeding, the forms being almost exclusively perennial.

The alpine flora is represented by thirty-four natural orders, of which thirty-one belong to phenogamous plants, the remaining three include the higher orders of Cryptogams; of the latter the ferns are represented · by a single species (Cryptogramna acrostichoides R. Br.), not exclusively alpine. Mosses are numerously represented, but are still comparatively rare, while lichens are most abundant and afford the greatest number of species.

The alpine area lying between the thirty-seventh and forty-first parallel of latitude, is from 1200 to 1500 square miles in extent. As a sanitary retreat during the summer months it is unexcelled in the purity and coolness of its atinosphere, the clearness of its flowing streams, and its picturesque, extended views.

Prof. E. D. COPE, in his paper “On the Larval Characters of the Urodela,” stated: 1st, That it is shown that one portion of the primary groups is inexactly parallel to larvel stages of the other portion. 211, That certain genera only fail of exact parallelism with larval stages of other genera by but two characters. 3d, That others lack but one character; and 4th, That others present an exact parallelism.

He had reason to think from the development of Amblystoma, and experiments on salamander and frog larvæ, that the process of growth or assumption of generic characters may be much retarded or accelerated. Such a process would produce the cases of exact parallelism; and if the retardation in the character should continue, would necessarily soon result in inexact parallelism in that respect, thus producing a complete metamorphosis of the genus. The reverse of this process is acceleration, and expresses the mode of progress of a type to its highest development in time history, while the retardation is the mode of its degradation.

Mr. Hyatt remarked that Prof. Cope's views were, so far as the law of acceleration was concerned, equally good among the shell-covered Cephalopods. Among these animals the shells of the species displayed the action of this law. He quoted from a previous publication in the * Memoirs of the Boston Society of Natural History,” in which this law had been distinctly stated. But farther than this that its action was also as forcibly displayed in the species itself as in the genus.

Mr. A. HYATT read a paper “On the Homologies and General Structural Relations of the Polyzoa.” The Embryology of the IIypocrepian Polyzoa show that Loxosoma is the lowest of all in the order, and together with Pedicellina form the lowest suborder of the group. The progress of the whole order of Polyzoa is from this permanently invaginated form through intermediate stages to Crisțatella, in which, when the polypiile is inserted, even the stomach is carried up beyond the orifice of the cell. Thus the progress of structure is from an animal in which all the organs are crowded into the anterior end, into the cænæcial system, and to one in which the cænæcial or reproductive, eraginatory or gastric, and the lophoric or neural systems are all distinct when the animal is exserted.

The Polyzoön may be transformed into a Brachiopod by simply enlarging the cenecial wall and carrying it over, inclosing the lophophore and reversing the position of the arms. Thus both the Polyzoa and the Brachiopods may be detined as sacs, closed at the posterior end by discs surrounded by tentacles, and perforated by an edentulous mouth, from which hangs the alimentary canal in the antero-posterior axis of the sac. The whole plan of the Mollusca was stated to be that of a simple sac, and the term Saccata proposed as more appropriate than that of Mollusca. The objection that the whole animal kingdom may be said to be sac-like AMER. NATURALIST, VOL. III.

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has been raised. The Radiata are, it is true, radiated sacs, the Articulata ringed sacs, and the Vertebrata sacs divided by the vertebral axis, but the Saccata are ally sacs.

Prof. THEO. GILL, in his communication “On New Species of Fishes obtained by Prof. Orton in the Valleys of the Maranon and Napo," concluded from the study of twenty-five species collected by Prof. Orton, that there were no distinct tish Paunæ in these river valleys, species of the same genera having been found distributed through them, some of the genera having also occurred lower down the Amazon, while one genus inhabited the fresh waters of Central America.

Dr. T. STERRY HUNT, in his remarks “On the Geology of North-eastern America,” exhibited a new geological map of the British Provinces, and of the United States as far South as Virginia, and West to near the base of the Rocky Mountains. He called attention to the uncolored portion represented by New England, and to the fact that less was known of the age of the rocks of that region than any other. He stated that he knew of no eruptive granitic rocks, but that with an occasional exception they were of sedimentary origin. Metamorphism depends on the original quality of the sediments; we cannot produce granite from sandstone, or dolomites from limestones, etc., etc. He cited a case observed in New Brunswick where the Dadoxylon sandstones are overlaid by granitoid and felspathic grits, and yet the Dadoxylon sandstones are unaltered. On lithological grounds he thought that the rocks about Lowell and Newburyport, containing thick beds of limestone, were of Laurentian age, and baving seen specimens of Labradorite, from boulders in Marblehead, in the Museum of the Peabody Academy, he suggested that there might be Laurentian rocks about Salem.

Messrs. MATTHEW and BAILEY, in their “Remarks on the Age and Relations of the Metamorphic Rocks of New Brunswick and Maine," after giving a summary of the labors of Gesner, Robb, Matthew, Dawson, Hitchcock, Bailey and Hartt in this region, describe the Laurentian, Huronian (or Cambrian), Lower and Upper Silurian rocks, and give a detailed description of that portion of the metamorphic area not occupied by the rocks above mentioned. This portion consists of Upper Devonian strata and granite, of which the latter forms, in New Brunswick, a ridge of variable width, having Devonian slates on both sides. The two together probably occupy three-quarters of the metamorphic country south of the New Brunswick coal-fields.

Two principal divisions of this series may readily be distinguished, on the south side of the granite ridge, viz. : (1) the Lepreau, comprising diorites, felsites, and conglomerates in its lower portions; and in the upper subdivision gray sandstones, black slates, and the Dadoxylon sandthese rocks lie the granite rock, and there appears to be a gradual passage from true granite, through felsites, to undoubted Upper Devonian slates, these Nerepis granites being probably altered sandstones and grits at the base of the Cpper Devonian series. The rocks south of the granite ridge were littoral, and those on the north were deposited in deeper waters, the rocks being much more uniform. In the partially inetamorphic states of the Lepreau division, plants and shells characteristic of the Upper Devonian have been found, and when more highly altered, well defined crystals of staurotide, andalusite and garnet.

To the lower division, viz. : (2) the Mispeck division, belong, in the lower subdivision, conglomerates and diorites, Cordaite, fine-grained slates and orthophyre; and in the upper subdivision conglomerate and slate, granitoid grit, talcoid (?) slates and limestone. At the base of

stones.

Having unexpectedly found that the greater part of the metamorphic country in New Brunswick, near the United States border, is of Upper Devonian age, the authors offered some suggestions and conjectures on the probable age of the schists, granites, etc., in the south-eastern half of Maine.

The granite ridge of southern New Brunswick enters the State of Maine at Calais, and is there represented by a thick body of conglomerate gneiss (composed of dark sienitic pebbles, from two inches to as many feet in diameter, enclosed in a white granitic, often porphyroid matrix), dark sienitic gneiss and white granite, which they believed to be Laurentian, and a mass of red, weathering, coarse granitoid rocks, which may represent those of the Nerepis, and perhaps constitute the basal portion of the Devonian. Both of these are probably represented in the granitic district of south-eastern Maine. To the eastward of this we appear to have chiefly Upper Devonian rocks, with occasional bands of upturned Upper Silurian rocks. The “traps” of this area correspond to the diorites, etc., at the base of the Mispeck division, and the red jasper to the red felsites and orthophyre above them. It is probable that the Lepreau divisions will be but meagrely represented, and the upper half of the Mispeck wanting in this tract, such being the case around the Passamaquoddy Bay.

On the north-west side of the granite ridge noted, we again meet in New Brunswick the Upper Devonian slates, now in their pelagic aspect. On the Maine border above Baring these consist of tiner gneiss and micaceous quartzite, the former dipping towards and abruptly meeting the gneiss conglomerate, above alluded to, within which, along the line of junction, small pieces of the Devonian gneiss are imbedded, as though fragments of the latter had sunk in the pasty mass. Farther north these Devonian beds are folded and dip northward, passing beneath a heavy body of tine greenish and grayisli inicaceous slates, which here represent the Cordaite shales, or Lower Mispeck beds.

A similar arrangement is indicated by Prof. Hitchcock, who represents the slates or schists north of Baring as lying in a basin between the granite ridge above named, and another which crosses the northern part of Washington County and is supposed to connect through the northern part of Hancock County with the granitic masses around Mount Desert on the coast. On the southern side of this last granitic ridge, and forming the northern side of the trough, are a series of beds described as quartz rock and calciferous mica schist, and which are said to be the same as those known to extend through York County, N. B., towards the Bay de Chaleur. This belt of rocks has been recognized, with essentially the same features, by Mr. Bailey on the St. John River above Fredericton, and about Grand Lake in the eastern Schoodic region in Maine.

The granites on the north side of this basin are overlaid by a gray gneiss holding bands of micaceous quartzite, which constitute the first rocks seen on the northern slope of the granitic mass. These may be the “argillo-micaceous sclists,” described by Prof. Hitchcock as holding a similar position in Maine and which are said to extend in an "essentially unaltered form to the Saco River.”-in fact nearly reaching the south-west corner of the State. At this end of the basin, where probably the lower beds are exposed, the rock contains garnets, staurotide and kyanite. Along the north-east side (in Northport) it holds andalusite. If these rocks represent here the Lower Lepreau series, as the mica schists, holding a similar position and containing the same minerals, do in the cen. tral parts of Charlotte County, the geology of this portion of the Province will he greatly simplitied.

There is a belt of granite associated with masses of obscurely stratified gneiss and beds of pyritiferous mica-schist extending along the Coast of Maine from Portland eastwards to the mouth of the Penobscot River, which, as described in Prof. Hitchcock's Report, resembles the Laurentian series of New Brunswick. With this exception, and possibly that of the belt of slates and quartzites which skirts the southern edge of the northern granite belt, nearly all the formations of south-eastern Maine might, on lithological grounds, be compared with those of the Upper Devonian series. Among these, however, may be islands or ridges of older rock, as is probably the case at some points along the eastern border.

PROF. E. D. COPE, read a paper “On two New Genera of Extinct Cetacea.” His observations embraced a description of the characters of a very large representative of the Dugong of the modern East Indian Seas which was found in a bed, either Miocene, or Eocene, in New Jersey. It was double the size of the existing Dugong, and was interesting as adding to the series of Asiatic and African forms characteristic of American Miocenes. Another type was regarded as remotely allied to Squalodon, but it was edentulous, and furnished with a broad shallow alveolus, either of a form left after shedding a tooth, or that adapted to a broad obtuse tooth. It constituted a remarkable new genus which was called Anopolonassa forcipata. It was found in post pliocene beds near Savannah. He also exhibited teeth of two gigantic species of Chinchilla which had been discovered in the small West India island of Anguilla, which has an area of about thirty square miles. The specimens were taken from caves and were thought to indicate post pliocene age. With them was discovered an implement of human manufacture, a chisel made from the lips of a shell, Strombus gigas. The contemporaneity of the fossils and human

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