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zone which covers it, the presence of the verrucano (or talco-quartzose conglomerate) between these two formations and the quantity of tale disseminated in all these rocks, present us problems which science is not able to solve completely."-(Studer, cited by Laugel, Bull. Soc. Geol. de France, [2], xii, 576.)

In the metamorphic rocks of the anthracitic system Gras distinguishes what he calls a protogine or talcose formation, consisting of granite, gneiss and mica slates, generally more or less talcose, containing also schistose diorites, eurites and leptynites. This protogine formation is intimately associated with the argillo-calcareous shales of the lower anthracitic series, which are found interstratified with and even passing into gneiss and other feldspathic schists. Gras concludes that this somewhat irregular interpenetration of the two classes of rocks is due to an irregular metamorphism, portions of the argillo-calcareous sediments having, as he supposes, been profoundly altered by emanations from below, and he hence regards the protogine formation as a portion of the inferior anthracitic series. Similar crystalline schists also occur in some parts of the upper anthracitic series, and in both the upper and lower there are found serpentines, euphotides, porphyries and spilites, all of which the author regards as of sedimentary origin, and as having undergone in situ a profound metamorphism which has often effaced the marks of stratification; this view he declares is the only one which appears to agree with the observed facts. This protest against the theory of the igneous origin of serpentines is in accordance with the results obtained by the Geological Survey of Canada; in his report for 1848 Sir William Logan insisted upon the sedimentary origin of the serpentines which occur in the altered palæozoic strata of the Green Mountains.

Rozet, in his investigations of the Alps, has referred to the liassic and jurassic periods the great system of gneiss, with micaceous and talcose schists, which makes up Mts. Cenis and Pelvoux, and a great part of the mountains of the frontier of Piedmont, while, according to Fournet, the jurassic rocks of the Valais have been altered in like manner. (Coquand, des Roches, pp. 300-301.)

Our author however supposes that all these altered strata are of carboniferous age, and remarks that the fossils in the limestone of the lower lias show but slight marks of metamorphism, from whence he concludes that "in this region of the Alps there are no highly metamorphosed jurassic rocks," and that the metamorphic action "which took place beneath the sea before the elevation of these mountains" ceased to be powerful after the deposition of the Valorsine conglomerate, (which he regards as of carboniferous age,) the paste of which is often converted into a crystalline talcose schist. At the same, although the liassic and so-called triassic rocks are comparatively unaltered, the jurassic shales are described as more or less talcose and greasy to the touch, but the alterations of these argillaceous rocks our author regards as rather mechanical than chemical." (p. 76.)

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The question before us is then, whether in that series of rocks which embraces liassic and jurassic beds with gypsum, dolomite, anthracite, and a carboniferous flora, and which geologists have generally referred to one great system not older than the lias, we have really in these mountains,

as Favre supposes, the whole succession of formations from the oolite to the carboniferous inclusive, so involved by foldings and inversions that it has hitherto been impossible to determine their real structure.

But even if we admit with Favre the paleozoic age of the protogine. formation described by Gras and Rozet, we cannot agree with him in limiting to the rocks of that period the action of the metamorphic process. The development of a talcose character in the jurassic shales we cannot regard as the result of a mechanical process, and we have besides evidences in the Alps of the metamorphism of still higher rocks.

As early as the year 1834 Keferstein had asserted that the granites of Mont Blanc are nothing more than altered strata of flysch, (Naturgeschichte des Erdkörpers, i, 286–292; Bul. Geol. Soc. de France, [1], vii, 198,) and in 1850 Sir Charles Lyell in his address before the Geological Society of London suggested that the protogines of the Alps might be of tertiary age. This is so far true that both Studer and Murchison have shown that portions of the eocene flysch have been converted into crystalline gneiss, mica slate and even granitic beds; Murchison, like Gras, whom we have already cited, remarks that the metamorphism seems irregular, some bands of the rock being apparently much more altered than others. (Geol. Journal, v, 164, 210.) The intercalation of wedgeshaped masses of fossiliferous limestone of liassic age among the gneissic strata of the Alps has been well described by Studer (Bul. Soc. Geol. de France, [2], iv, 208), and similar phenomena observed in various other metamorphic regions present a problem the right understanding of which is most important in its relations to the theory of metamorphism, and one which we propose to consider at an early day.

In conclusion we hasten to say, that although dissenting from some of the views of Mr. Favre, we are not less grateful for his very suggestive memoir, which with its carefully prepared lists of fossils and its beautiful sections is a valuable contribution to alpine geology.

T. STERRY HUNT.

2. The Geological Structure of the "Jornada del Muerto," New Mexico, being an abstract from the Geological Report of the Expedition under Capt. John Pope, U. S. Top. Eng., for boring Artesian Wells along the line of the 32d parallel; by G. G. SHUMARD, M.D., Geologist of the Expedition, (Trans. Acad. Sci. St. Louis, vol. i, No. 3, p. 341. 1859).-This paper gives a description of the geological structure of a district of country lying immediately east of the Rio Grande, and between the 32d and 34th parallels. The "Jornada del Muerto" is described as a gently sloping plane, of an elliptic form, from twelve to forty miles in breadth, and extending from near the southern extremity of the Doña Ana Mountains eighty or ninety miles in a N.N.W. direction. It is bounded on the east and west by ranges of mountains, varying in their elevation from two or three hundred to one thousand feet above the plane, and seem to be mainly composed of dark colored limestones of Upper Carboniferous age, dipping towards the interior of the intermediate plane; these rocks however, in the western range, were observed at some places, surmounted by shales and sandstones referred to the Cretaceous epoch. Igneous rocks form a belt of low hills along the eastern side of the eastern range, and also occur between the other and the Rio Grande. From the structure of

the surrounding country, the "Jornada" is supposed to be a great synclinal depression, in which water could probably be obtained by artesian borings, through heavy detrital deposits.

The fossils found in the Carboniferous rocks here, and in the Organ Mountains, are all Upper Carboniferous types, many of them being identical with species almost everywhere common in the western Coal Measures. Those mentioned in the Cretaceous beds are Inoceramus and Cardium. The paper also contains interesting local details in regard to the igneous and metamorphic rocks of the several mountain ranges explored.

M.

3. Notice of Fossils from the Permian strata of Texas and New Mexico, obtained by the United States Expedition under Capt. John Pope, for boring Artesian Wells along the 32d parallel, with descriptions of new Species from these strata and the Coal Measures of that region; by B. F. SHUMARD, M.D., (Trans. Acad. Sci. St. Louis, vol. i, Part 3d. 1859).— This is an important paper, containing descriptions of many new species, with an enumeration of others identified with forms known in the Kansas rocks, and of a few which are, by the author, supposed to be identical with foreign species; it is also illustrated by an excellent plate of twentyseven figures by Leopold Gast & Brother of St. Louis.

Most of these fossils are from an extensive deposit of white limestone, and inferior beds of sandstone and darker colored limestone, in the Guadalupe Mountains, referred by Dr. S. to the Permian System. The new species described from these rocks are―

Campophyllum? Texanum, Chonetes Permiana, Spirifer Guadalupensis, Terebratula perinflata, Rhynchonella indentata, R. Texana, Camerophoria Swalloriana, Crania Permiana, Arinus securis, Turbo Guadalupensis, Pleurotomaria Halliana, and Chemnitzia Swalloviana. Those from the beds regarded as Carboniferous, are Turbo Texanus, Straparollus cornudanus, Pleurotomaria Proutiana, P. obtusipira, P. perornata and Machrocheilus Texanus.

All of which appear to be described with the author's well known care and accuracy.

Dr. S. had previously described from the beds he places in the Permian, Phillipsia perannulata, Fusulina elongata, Productus Mexicanus, P. pileolus, P. Popei, Strophalosia (Aulosteges) Guadalupensis, Spirifer Mexicanus, S. sulciferus, Spiriferina Billingsii, Terebratula perinflata, Rhynchonella Guadalupe, Camerophoria bisulcata, Retzia papilata, R. Meekiana, and Myalina recta,

several of which are well illustrated in the plate accompanying the paper now under consideration. He also gives the following list of forms from these rocks, regarded by him, with more or less confidence, as identical with species occurring in the Permian and Upper Carboniferous beds of Kansas, viz:

Acanthocladia Americana, Productus Calhounianus, P. Norwoodii, Spirifer cam eratus, Streptorhynchus (Orthisina) Shumardianus, Edmondia suborbiculata, and Pleuraphorus occidentalis; while he thinks he recognizes the following foreign species in the same association :-Chatetes Mackrothii, Productus semireticulatus, var. antiquatus, P. Leplayi?, Terebratula elongata, Camerophoria Schlotheimi?, Myalina squamosa, Monotis Speluncaria, and Turbo helicinus?.

As Dr. S. finds a Phillipsia and a Fusulina, in these rocks, neither of which genera are known to range up into Permian beds in the old world, and Spirifer cameratus is a characteristic Coal-measure species, from Pennsylvania to the Rocky Mountains; while Productus semireticulatus,

is regarded by most authors as peculiar to the Carboniferous systemand a large proportion of the other species mentioned as common to the New Mexican and Kansas rocks, are known to occur in the latter territory in beds containing even a majority of well marked Coal-measure species, we may infer that in New Mexico, as in Kansas, there is a considerable blending of Carboniferous and Permian types; so that it becomes a matter of doubt and difficulty to determine at what particular horizon the line of demarkation should be drawn between these two Systems, if indeed there is any such natural break in our upper Palæozoic series of this country. It is to be hoped Dr. S. will continue his investigations of the fossils occurring in these formations, which he will doubtless have an opportunity to do, in connection with the geological survey of Texas, under his charge.

M.

4. Observations on the Geology of the County of Ste. Geneviève, being an extract from the Report made to the Missouri Geological Survey, in 1859; by B. F. SHUMARD, M.D., (Trans. St. Louis Acad. Sci., vol. i, part 3, page 404, 1859.)-In addition to information respecting the iron and lead mines, building materials, &c., of the county, this extract contains some facts having an important bearing on mooted points in the classification of the Lower Carboniferous Series of the West. Dr. S. found this series to be composed of the following members, in the descending order: 1st. THE UPPER ARCHIMEDES LIMESTONE, characterized by Pentremites pyriformis, P. sulcatus, Agassizocrinus dactyliformis, Spiriferina spinosa, Spirifer trigonalis, and species of Archimedipora. 2d. THE FERRUGINOUS SANDSTONE, in which no fossils were found,-estimated thickness, 80 to 100 feet. 3d. THE STE. GENEVIEVE LIMESTONE, a second Archimedes bed, in which the following fossils were found:-Rhynchonella trimela, R. Wortheni, Spirifera hirsuta, Retzia Mareyi, Spiriferina spinosa, Spirifera Leidyi, Productus elegans, P. bisulcatus, Murchisonia vermicula, Pentremites florealis, and one or more species of Archimedipora.

4th. THE SAINT LOUIS LIMESTONE-containing Lithostrotion mammillaria, Archacidaris and Pentremites conoides,-thickness 100 feet or more.

5th. THE THIRD ARCHIMEDES LIMESTONE, containing Pentremites laterniformis, P. conoides, Archimedipora, Dichoerinus simplex, Spirigera hirsuta, Productus Indianensis, Rhynchonella subcuneata, and Holopea Prouti,-thickness from

100 to 150 feet.

6th. THE ENCRINITAL LIMESTONE (= Burlington LIMESTONE), with its usual fossilsbeing the lowest member of the great Carboniferous series.

Of the Devonian rocks he recognizes the CHEMUNG GROUP, HAMILTON GROUP, and the ORISKANY SANDSTONE. Of the Silurian-1st. Lower HELDERBERG SERIES, 2d. The NIAGARA GROUP, 3d. The HUDSON RIVER GROUP, 4th. The RECEPTACULITE LIMESTONE, 5th. The TRENTON LIMESTONE, 6th. The BLACKRIVER and BIRDSEYE LIMESTONES. Then comes the five members of the GREAT MAGNESIAN LIMESTONE SERIES, which represents the Calciferous, and possibly portions of the Potsdam and Chazy Limestones of New York; and last of all, eruptive rocks.

Of the Coal measures, only thin outliers cap the hills half a mile above St. Mary's on the Mississippi. The beds are alternations of shale and sandstone, surmounted by a thin bed of hard siliceous limestone.

M.

5. Third Series of Descriptions of Bryozoa, from the Paleozoic Rocks of the Western States and Territories; by H. A. PROUT, (Trans. Acad. Sci. St. Louis, vol. i, part 3, p. 443, 1859.)--Every geologist who has

worked amongst western rocks, must have regretted that Paleontologists have generally given so little attention to the remains of Polyzoa characterizing these formations. These delicate forms of life existed in great profusion during portions of the Paleozoic era, especially during the deposition of some of the lower members of the great Carboniferous series, and are often met with in a good state of preservation, where no other organic remains are to be seen., Consequently when accurately classified, and the species and genera are fully described and illustrated,due care being taken to determine the exact geological position of each,— they will at once become an important guide in the identification of strata. The task of classifying, describing, and illustrating these remains occurring in the western rocks, has been undertaken by Dr. Prout of St. Louis, who has produced several valuable papers on this subject, previous to the publication of that now under review. His last paper, mentioned at the head of this notice, contains full descriptions of nine new species, and two new genera, with four beautiful plates illustrating these and some of the species described in his former papers. These plates are engraved on stone by Leopold Gast and Brother, of St. Louis, from drawings by Dr. Prout and Mr. Gast, and bear evidences of skill and accuracy. The new genera described in this paper are Semicoscinium and Septopora, and the new species, Semicoscinium rhomboideum, Fenestella hemitrypa, F. banyana, Limaria falcata, Flustra spatula, F. tuberculata, Septopora Cestriensis, and Polypora tuberculata.

Dr. S. also thinks he has identified a Permian species, Polypora biamica of Keyserling, in the Upper Archimedes Limestone, a member of the Lower Carboniferous Series, at any rate no essential differences were observed in the specimens compared. It is probable however, that when better specimens are obtained, showing all the characters of this Lower Carboniferous form, it will prove distinct from the Permian species.

III. BOTANY AND ZOOLOGY.

M.

1. Collections of Cuban Plants.-Mr. Charles Wright revisited the eastern part of Cuba in the autumn of the year 1858, where he still remains, engaged in botanical explorations in that little-known region. His collections of dried plants, up to last autumn, have already been received; and the Ferns, which form a large and very attractive part of them, have been distributed into sets. A number of these sets, not yet appropriated, are offered for sale. The fullest of these sets contain about 180, the smallest 120 species, which may be increased by further collections to a moderate extent. Sets can be obtained from Professor Gray, Cambridge, at $10 per hundred specimens. Of phænogamous plants, soon to be distributed, a very few sets are still open to subscribers, at the same price. It is expected that the species will be named very soon. The names of the ferns are about to be published by Mr. Eaton of New Haven, our principal Pteridologist. The rich collections in the lower Cryptogamia, made by Mr. Wright in his former visit to Cuba, along with those of the present exploration, are now in course of study, the Musci and Hepatica by Mr. Sullivant, the Lichenes by Prof. Tuckerman, the Fungi by the Rev. Dr. Curtis, preparatory to their distribution in

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