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DRIESCH, H. AND T. H. MORGAN.—Zu. Analysis der Ersten Entwickelungsstadien des Ctenophoreneies. Aus Archiv für Entwickelungsmechanik des Organismen, II Bd., 2 Heft. Leipzig, 1895.

DURAND, J. P.-Questions Anthropologiques et Zoologiques. Extr. Bull. Soc. Anthropol., Paris, 1895.-Genèse Naturelle des Formes Animales. Extr. Revue Scientif., 1888. From the author.

Essarts, A.-Aperçu historique sur la doctrine du Polozoism humain. Extr. Journ. des Inventeurs. Paris, 1895. From the author.

Exhibit of the Smithsonian Institution at the Cotton States Exposition, Atlanta, 1895.

FRASER, A.-A Case of Porencephaly. Extr. Journ. Mental Sci., 1894.

- Morphological Papers. Extr. ns. Roy. Acad. Med. in Ireland, Vol. XII, 1895. From the author.

FRAZER, P.-In Memoriam, Edward Yorke Macauley, Rear Admiral U. S. N. Extr. Proceeds. Amer, Philos. Soc., Vol. XXXIV. From the author.

GOODE, G. B.-An Account of the Smithsonian Institntion. Its Origin, History, Objects and Achievements. Washington, 1895.

JANET, C.-Sur Vespa media, V. silvestris et V. saxonica. Extr. Mém. Soc. Acad. de l'Oise T. XVI, 1895.

Sur l'Organe de nettoyage tibio-tarsien de Myrmica rubra L. race levinodis Nyl. Extr. Ann. Soc. Entomol. de France, Vol. LXIII, 1894.

-Sur Vespa germanica et V. vulgaris. Limoges, 1895.
-Sur les nids de la Vespa crabro. Extr. Comptes rendus, Paris, 1894.
-Sur la Vespa crabro. Conservation de la chaleur dans le nid, 1 c., 1895.

-Observations sur les Frelons. L. C., 1895. From the author.
KEDZIE, R. C.-Fertilizer Analyses. Bull. 126, Michigan State Agric. Coll.
Exper. Station.

KEMP, J. F.-Crystalline Limestones, Ophicalcites and associated Schists of the Eastern Adirondacks. Contrib. Geol. Dept. Columbia Coll. No. XXVII, 1895. From the author.

LAHILLE, F.-Contribucion al Estudio des las Volutas Argentinus. Extr. Revista Mus. de la Plata, T. VI, 1895. From the author.

LE CONTE, J.-Critical Periods in the History of the Earth. Extr, Bull. Dept. Geol. Univ. California, Vol. I, 1895.

LEVY, L. E.—The Russian-Jewish Refugees in America. Philadelphia, 1895. From the author.

MERCER, H. C.-Re-exploration of Hartman's Cave, near Stroudsburg, Pennsylvania, 1893. Extr. Proceeds. Phila. Acad. Nat. Sci., 1894. From the author.

MIDDLETON, C. S.-Annual Address. Extr. Trans. Penna. Homeopath. Med. Soc., 1895. From the author.

MITSUKURI, K. AND S. IKEDA.—Notes on a gigantic Cephalopod. Extr. Zool. Mag., Vol. VII, 1895.

MORGAN, T. H.—The Fertilization of non-nucleated Fragments of Echinoderm Eggs. Experimental Studies of the Blastula und Gastrula Stages of Echinus,

Aus Archiv für Entwickelungsmechanik der Organismen, II. Bd. 2 Heft, Leipzig, 1895. From the author.

OLIVER, C. A.-A Short note upon so-called “Hereditary Optic Nerve Atrophy" as a Contribution to the Question of Transmission of Structural Peculiarity. Extr. Proceeds. Amer. Philos. Soc., Vol. XXXII.

Scott, W. B.-Protoptychus hatcherii, a new Rodent from the Uinta Eocene. Extr. Proceeds. Phila. Acad. Nat. Sci., 1895. From the author.

SHIPLEY, S. R.-Gold, Silver and Money. Extr. Amer. Friend, 1895. From the author. Stiles, C. W.-Notes on Parasites 32, 33, 34, 38 and 39. Extr. Veterinary

1895.- -The Anatomy of the large American Fluke, Fasciola magna and a comparison with other species of the genus Fasciola, S. St. with a list of the chief Epizootics of Fascioliasis, and a Bibliography of Fasciola hepatica by Albert Hassall. Extr. Journ. Comp. Med. & Veterinary Arch., 1894–1895. From the author.

WHITE, C. A.-The Bear River Fauna and its Characteristic Fauna. Bull. U. S. Geol. Surv., No. 128. Washington, 1895. From the author.

Wilson, E. B.-An Atlas of the Fertilization and Karyokinesis of the Ovum. New York and London, 1895, Macmillan & Co. From the author.

Mag,

General Notes.

PETROGRAPHY

The Eruptives and Tuffs of Tetschen.-Two interesting articles on the area of crystalline rocks east of Tetschen on the Elbe, have appeared simultaneously. The first, by Hibsch, is a description of the Tetschen’ sheet of the map of the Bohemian Mittlegebirges, and the second by Graber, is on the fragments and bombs occurring in the tephrite tuffs of the region.

The volcanic rocks of the district are interbedded basalts, tuffites, tuffs and tephrites, of which the fragmental rocks are in greatest abundance. Augitites also occur as sheets, and camptonites as dykes in upper Cretaceous marls. The older igneous rocks are granitites and diabases that are associated with clay slates, probably of Cambrian age. Analyses of each of these rocks are given but the rocks are not described in detail. The greater portion of the author's article deals with the volcanic rocks. The tuffs are composed of basaltic and tephritic fragments of the coarseness of sand in some cases, and in others of

· Edited by Dr. W. S. Bayley, Colby University, Waterville, Me.
* Min. u. Petrog. Mitth., XV, 1895, p. 201.
* Ib., p. 291.

pieces several feet in diameter. These are cemented together by finer
portions of the same substances, among which have been deposited zeo-
lites, carbonates, opal and other secondary minerals. Some beds of
this tuff are so filled with large fragments of basalt, tephrite, etc., that
the rock composing it has been called the “Brocken Tuff." It is to
the study of the fragments in this tuff that Graber's paper is devoted.

The basalts and tephrites constitute sheets and lava streams that are
interstratified with the tuffs and sediments. Among the former rocks
are noticed feldspathic, leucitic and nephelinic varieties, besides in
several places magma-basalts. In addition to sheet basalts, dykes and
chimneys of this rock have also been observed.

The rocks in all their forms are normal in their development. The author regards contact action around the chimneys as the safest criterion by which to distinguish these forms from denuded sheets and flows. The tephrites comprise hauyn-tephrites, in which hornblende and aegerine are present, nepheline-tephrite, including trachytic and andesitic varieties, and leucite-tephrite composed of phenocrysts of augite, plagioclase and grains of magnetite in a groundmass of these same components, and leucite, biotite and nepheline.

The augite consists of two generations of magnetite and augite in a glassy base. Its analysis gave:

SiO, TiO, P,0, A1,0, FeO, FeO CaO MgO K,0 Na,O H,0 Moisture Total 13.35 1.43 1.54 11.46 11.98 2.26 7.76 11.69.99 3.88 2.41 .59 =99.34

The feldspathic basalt and the andesitic tephrite are the only rocks
that seem to have affected the sediments with which they are in con-
tact. Quartzites are changed to aggregates of quartz grains in a glass
matrix, where the action is not extremely severe, and to an aggregate
of interlocking quartz grains where it has been intense. The article
closes with an account of the detailed results of analysis of ten speci-
mens of the volcanic rocks.

Graber's article is devoted principally to a description of the frag-
ments found in the Brocken-tuff. These are all tephritic rocks, among
which andesitic, leucitic and phonolitic types are recognized. The
characteristics of the components of all these types are portrayed in
great detail, especial care being given to the descriptions of the augite
and the plagioclase. The phonolitic tephrite is characterized by the
presence of nosean, which is in irregular grains. In the andesitic teph-
rite, which is the most basic variety, the porphyritie augite has an ex-
tinction angle cAC of 580-62o, in the leucitic type its extinction is

52°-56° and in the phonolitic type, the most acid variety, it is 50053°. In each of the types labradorite and sometimes oligoclase phenocrysts are common, but the feldspar of the groundmass differs in character in the different types. In the andesitic type it is oligoclase, in the leucite variety andesine, and in the phonolitic type sanidine.

A Nepheline-Syenite Bowlder from Ohio.-Miss Bascom has found in the drift near Columbus, Ohio, a bowlder which consists of nepheline-syenite porphyry. The rock is composed of large phenocrysts of oligoclase and smaller ones of nepheline, augite, hornblende and olivine in a groundmass composed of plagioclase and orthoclase laths, hornblende, biotite, augite and magnetite in a feldspathic matrix.

Crystalline Rocks of New Jersey.-In a report on the Archean Highlands of New Jersey, Westgate states that the northern balf of Jenny Jump Mt., Warren Co., consists mainly of gneisses with a small area of crystalline limestone, diorites, gneisses, etc. The gneisses are granitoid biotite-hornblende varieties, biotite.gneisses and hornblende-pyroxene gneisses. In the first named variety the prevailing feldspars are microcline and microperthite, and in the pyroxene gneisses plagioclase and orthoclase. The gneisses are cut by pegmatite dykes, amphibolites and diabases.

Associated with the white crystalline limestones are fibrolite and biotite gneisses, hornblendic gneiss, amphibolites, gabbros, norites and diorites, most of the latter of which show evidence of an eruptive origin. Another type of rock often found associated with the limestones is a quartz-pyroxene aggregate, in which the pyroxene is a green or white monoclinic augite. The limestone, the fibrolite and biotite gneisses and the quartz-pyroxene rock are thought to be metamorphosed sediments.

Simple Crystalline Rocks from India and Australia.-Judd gives us an account of several simple crystalline rocks from India and Australia. One is a corundum rock composed principally of corundum grains with rutile, picotite, diaspore and fuchsite as accessory constituents. The corundum is in part pale colored and in part strongly pleochroic. The grains of the latter extinguish together producing with the former a micro-poicilitic structure. One of the specimens examined came from South Rewah and the other from the Mysore State.

"Journ. Geol., Vol. IV, p. 160.

5 Ann. Report State Geol. of New Jersey for 1895. Trenton, New Jersey, 1896, p. 21-61.

6 Mineralogical Magazine, Vol. XI, p. 56.

Associated with the corundum in the Mysore State is a fibrolite rock.
A tourmaline rock from the Kolar gold field in the same State and
from North Arcot and Salem in Madras, consists of twisted and bent
tourmaline fibres in a matrix of smaller fibres of the same substance.
In the neighborhood of Bingera, New South Wales, two rocks are
found as dykes cutting serpentine. One consists almost exclusively of
green garnets and the other of picotite. The former contains also gold
and chrysocolla.

The Weathering of Diabase.--Mr. Merrill' describes the changes
that have been effected in a granular diabase at Medford, Mass., during
its disintegration into soil. Bulk analysis of the fresh and the weath-
ered rock yielded the following results :

SiO, A1,0, Fe,0, FeO Cao MgO MnO K,0 Na, P,0, Ign Total Fresh 47.28 20.22 3.66 8.89 7.09 3.17 .77 2.16 3.94 .68 2.73=100.59 Weathered 44.44 23.19 12.70 6.03 2.82.52 1.75 3,93 .70 3.73= 99.81

The disintegration of the rock is accompanied by a leaching out of its
most soluble constituents. Assuming that the alumnia has remained
unchanged in quantity in the course of the disintegration, the percent-
age of each constituent lost in this process is shown to be as follows:
SiO, A1,0, Fe,O, FeO Cao MgO MO K,0 Na, P,O, Ign
18.03 .00 18.10 25.89 21.70 41.57 29.15 12.83 11.39 .00

The paper is full of valuable suggestions that cannot be even referred
to in these notes.

Petrographical Notes.--Transitions from massive anorthosites into augen gneisses and into thinly foliated gneisses and transitions from olivine gabbro into hornblende schists are briefly described by Kemps in a preliminary article on the dynamic metamorphism of anorthosites and related rocks in the Adirondacks.

Pirssono suggests the use of the word anhedron to express the meaning usually expressed in the phrase by pidiomorphic form.' An anhedron is a body with the physical constitution and properties of a crystal but without the crystallographic form. The term may be conveniently applied to the crystalline grains in rock masses.

- Bull. Geol. Soc. Amer., Vol. 7, p. 349.
* Bull. Geol. Soc. Amer., Vol. 7, p. 488.
" Ib., Vol. 7, p. 492.

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