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Annual Report of the Yorkshire Society for 1895. York, 1896. From the Society.

MOORE, C. B.-Certain Sand Mounds of Duval Co., Florida.-Two Mounds on Murphy Island, Florida.

-Certain Sand Mounds of the Ocklawaha River, Florida. From Advance Sheets of the Journ. Acad. Nat. Sci., Phila., Vol. X. Phila., 1895. From the author.

NORRIS, W. F.—The Terminal Loops of the Cones and Rods of the Human Retina with Photomicrographs. Reprint from Amer. Ophathalmol. Soc., Trans. 1895.

ORDONNEZ, E.- Las Rocas eruptivas del suroeste de la Cuenca de Mexico. Extr. Bol. Inst. Geol. de Mexico., Mun. 2. Mexico, 1895. Erom the Inst.

PALMER, T, S.-The Jack Rabbits of the United States. Bull. No. 8, U. S. Dept. Agric. Div. Ornith. and Mammalology. Washington, 1896.

PARKER, E. W.- Asbestos and Soapstone in 1892. Abstract from Mineral Resources of the United States, calendar year, 1892. Washington, 1893. From the U. S. Geol. Survey.

-The Production of Salt. Extr. Sixteenth Ann. Rept. U. S. Geol. Surv. 1894-95, Pt. IV. Mineral Resources of the U. S. Washington, 1895. From the U. S. Geol. Surv.

PEALE, A. C.--The Production of Mineral Waters. Extr. Sixteenth Ann. Rept. U. S. Geol. Surv., 1894–95, Pt. IV. Washington, 1895. From the U. S. Geol. Sury.

PIETTE, ED.-Hiatus and Lacune Vestiges de la Période de Transition dans la Grotte du Mas-d'Azil. Extr. Bull. Soc. d’Anthropol. Paris, 1895 From the the author.

Report of the American Humane Assoc. on Vivisection in America adopted at Minneapolis, Minn., Sept. 26, 1895. Chicago, 1896.

Report of the Meeting held for the Presentation to Professor Bonney of his Portrait, presented by his former pupils. London, 1895.

RIDGWAY, R.--Description of a New Subspecies of the Genus Peucedromus, Cones. Extr. Proceeds. U. S. Natl. Mus. From the Museum.

SHALER, N. S.—Peat Deposits. Extr. Sixteenth Ann. Rept. U. S. Geol. Surv., 1894-95. Pt. IV. Mineral Resources of the United States. Washington, 1895. From the U. S. Geol. Surv.

SIMPSON, C. P.--Description of Four New Triassic Unios from the Staked Plains of Texas Extr. Proceeds. U. Ş. Natl. Mus., Vol. XVIII, 1895. From the Museum.

SUMNER, F. B.—The Varietal Tree of a Philippine Pulmonate. Reprint from Trans. N. Y. Acad. Sciences, Vol. XV, 1896. From the author.

SWANK, J. M.--Iron and Steel and Allied Industries. Extr. Sixteenth Ann. Kept. U. S, Geol. Surv., 1894–95, Pt. III. Washington, 1895. From the U. S. Geol. Surv.

WILLISTON, S. W.-On the Skull of Ornithostoma. Extr. Kansas University Quarterly, Vol. IV, 1896. From the author.

General Notes.

PETROGRAPHY.

The Sioux Quartzite of Iowa.-The Sioux quartzite bas long been known as the oldest sedimentary rock in Iowa. It has recently been studied by Beyer. It is a white or red vitreous rock with which is associated as its upper extension a series of mottled reddish or purplish-black slates. The quartzites present the usual aspects of indurated sandstones. The constituent quartz grains are rich in quartzneedles' which can be traced directly into rutile spicules. The slates are arenaceous. They exhibit no traces of slaty cleavage, though in some cases their quartz grains and micaceous constituents are distorted in such a way as to testify to a horizontal movement in the rock mass containing them. All the slates are mottled by spheroidal masses of a lighter color than the body of the rock. These masses are spheroidal with the longer dimensions of the spheroids in the bedding planes of the shale. Their lighter color is supposed to be due to the removal of iron from those portions of the rock they occupy. Associated with the quartzites is a great mass of olivine diabase consisting of a coarse grained aggregate of labradorite and oligoclase zonally intergrown, olivine, augite, biotite, hornblende, apatite and magnetite. Most specimens are much altered, the components having been changed into the usual secondary substances common to diabase. In structure the rock varies from the ophitic, in which the plagioclase is older than the augite, to the gabbroitic, in which the augite is the older mineral. An analysis gave:

Sio, TiO, Fe,O, FeO A1,O, CaO MgO K,O Nа,0 H,0 P,0, 42:85 tr 13.66 20.23 6.85 3.42 1.90 5.78 .88 tr

Total 100.57

The Peridotites of North Carolina. In connection with a dis. cussion of the occurrence and origin of corundum in North Carolina, Lewisgives us an interesting account of the basic rocks associated with the gneisses in that portion of the Appalachian belt included with. in the limits of the State. These basic rocks, consisting mainly of

Edited by Dr. W. S. Bayley, Colby University, Waterville, Me.
? Iowa Geol. Survey, Vol. VI, p. 69.
3 Bull. No. 11, North Carolina Geol. Survey, 1896.

1

peridotites, occur in small lenticular masses or in narrow strips, which are always enveloped in a sheet of schistose talc or chlorite, and thus are never in direct contact with the gneisses through which they are believed to cut. They are classed as peridotites, pyroxenites and amphibolites, the former being the most common. The peridotites present several types in each occurrence, all merging into one another and forming a single geological unit. The principal types of the peridotites are dunite, harzburgite, amphibole-picrite and forellenstein. All are massive, as a rule, though exceptions are noted. The dunite is composed of olivine grains, octahedrons and rounded grains of picotite and chromite, plates of enstatite, prisms of light green hornblende and various alteration products of these, the most common being serpentine tremolite and chlorite. The Harzburgite and the other peridotites present no unusual features. They appear to be transition phases between the dunite and the various pyroxenites among which are recognized two types, an enstatite rock and websterite. The enstatite rock is made up almost exclusively of enstatite or bronzite and its alteration product talc. An analysis of the enstatite gave:

SiO, A1,0, FeO Cao MgO MnO H,0 Total

51.64 .12 9.28 .45 31.93 .56 5.45 99.43 The amphibolites are composed chiefly of amphibole. The most important type is composed of grass-green hornblende, anorthite and more or less corundum. The rock is fine grained and it is usually gneissic, although occasionally massive. Transitions through forellenstein into dunite were observed, although the distribution of the rock suggests its occurrence in a system of dykes cutting the latter rock. The hornblende has the following composition : SiO, A1,0, Cr,O, FeO Nio MgO CaO NaO KO H,O Total 45.14 17.59 .79 3.45 .21 16.69 12.51 2.25 .36 1.34 - 100.33 Genth called the mineral smaragdite. Dana regards it as edenite. In addition to the rocks mentioned above, there are also present in the region massive serpenite, which was unquestionably derived from dunite, talc-schists, and soapstones derived from enstatite rocks and chlorite schists.

In a second paper the same author gives his reasons for considering these rocks as eruptive in origin.

Shales and Slates from Wales.--Hutchins continues his studies of clays, shales and slates by an investigation of the nature of shales taken from some of the deepest coal mines in Wales. The chemical composition of the particular shale analyzed does not differ materially from that of some of the carboniferous shales from other coal fields. Physically the deeper shales are not much more compact than hard clays. The author reviews the results of his observations on shales and slates. He states that what takes place in a rock during its progress from clay to shale, is the development and crystallization of muscovitic mica and the production of chlorite. He also calls atten. tion to the fact that dynamic metamorphism is made to explain many phenomena connected with the crystallization of slates, that are capable of being explained better by static metamorphism. The spots of many contact rocks are now thought to be secretions from a mineralizing solution, depositing in these spherical forms material collected from the rock body. By crystallization the spots pass over into cor. dierite, biotite or staurolite crystals.

* Elisha Mitchell Sci. Soc. Jour., Pt. II, 1895, p. 24. 5 Geol. Mag., Vol. III, 1896, p.

Notes.-Cushing declares that in addition to the rocks described by Kemp from the eastern Adirondacks there is a system of diabase dykes, which are older than the monchiquites and camptonites of the district.

By melting certain rock powders in the presence of reagents Schmutz has obtained aggregates of minerals which in most cases are very different from those composing the original rocks. Eklogite fused in the presence of calcium and sodium fluride yielded a mass of meionite, plagioclase and glass; leucitite with calcium chloride gave a mass com. posed of a glassy groundmass and plagioclase ; with the addition of sodium fluride and potassium silico-fluride it yielded scapolite, mica, magpetite; with sodium chloride it produced augite, scapolite and mag. netite and a glass matrix. Granite fused with magnesium and calcium chlorides and sodium fluoride gave andesine and olivine in a groundmass containing augite. Other rocks treated with other reagents gave analagous results.

As the result of a series of experiments made with the view of discovering a medium with a very high specific gravity that will not attack sulphides, Retgersø finds that the acetate and the mixed nitrate and acetate of thallium are both neutral toward sulphides. The former is available for separating minerals with a density below 3.9, and the latter those with a density below 4.5.

6 Trans. N. Y. Acad. Sci., XV, 1896, p. 249. 7 Neues Jahrb. f. Min., etc., 1896, I, 8 Neues Jahrb. f. Min., etc., 1896, I, p. 213.

P. 211.

In an article in the Neues Jahrbuch Bauer gives a German transscription of his article on the rocks associated with the jadeite of Turmaw, Burmah.

Schroeder vander Kolk" describes briefly a series of rocks collected by Martin in the Moluccas. In the southern part of Amboina the rocks are mainly granite and peridotite, while in the larger northern part they consist of modern volcanics, as they do also on the other islands studied. These rocks are principally dacites and liparites, but on one island andesites occur. Both the dacites and the granite contain cordierite. The dacites are pyroxene and biotite varieties. The andesites are pyroxenic; mica schists, breccias and limestones occur also on the islands. The residue left after treatment of the limestone with acid contains quartz, sanidine, plagioclase, biotite, amphibole, orthorhombic pyroxene, hematite, garnet, cordierite, sillimanite and pleonost.

BOTANY.

The Evolution of a Botanical Journal. In November of the present year the Botanical Gazette reaches its majority, by attaining the age of twenty-one years. It first appeared in November, 1875 under the name of the Botanical Bulletin, and consisted of four pages of short notes. It was edited by John M. Coulter, then professor of Natural Sciences in Hanover College (Hanover, Indiana). In his introductory note the editor stated that the object of the new journal was “to afford a convenient and rapid means of communication among botanists. The context shows that it was started as a distinctly western journal, intended to supplement the work of eastern botanical publications.

The first volume included notes by the editor, and Thomas C. Porter, Samuel Lockwood, G. C. Broadhead, M. S. Coulter, Mary E. Pulsifer Ames, J. T. Rothrock, H. C. Beardslee, Coe F. Austin, George Vasey, Alphonso Wood, Isaac Martindale, Elihu Hall, E. A. Rau, and others who have long since diappeared from the botanical field. With the

9 Neues Jahrb. f. Min., etc., 1866, I, p. 19.
19 Cf. AMERICAN NATURALIST, June, 1896, p. 478.
11 Ib., 1896, I, p. 152.
1 Edited by Prof. C. E. Bessey, University of Nebraska, Lincoln, Nebraska.

? Read before the Botanical Seminar of the University of Nebraska. October 10, 1896.

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