4. The Laccolitic Mountain Groups of Colorado, Utah and Arizona; by WHITMAN CROSS. 14th Ann. Rep. U. S. Geol. Surv. Washington, 1895, p. 157-241.-This work represents a general summation of the author's studies extending over a period of years upon the Anthracite and Crested Beetle districts of Colorado, where the opportunities for the study of laccolites on ant extended scale are especially fine. In doing so he has been led to a general study of the literature upon this subject and has collated all the facts bearing upon the occurence of these intruded masses of igneous rocks in the plateau region of Western America so far as known. The paper opens with a review of Gilbert's work in the Henry Mts. and with a definite restatement and affirmation of the principles laid down by that investigator. Following this the work of the earlier geological explorers in this region, especially Holmes and Peale, is reviewed, and it is shown that many of the detached mountain groups visited by them are to be referred to this mode of origin. The author then presents in detail the result of his own studies in the field mentioned above, and concludes with a general statement of principles. Especially valuable are the results showing the asymmetric form of laccolites when intruded into strata already flexed and under compressive stresses or tensional strains or containing resistant masses of former intrusion. It is of interest also to note the extremely uniform type of rock in these occurrences over such a vast range of country. Mr. Cross shows also that a certain type of rock structure is a nearly constant resultant of the processes involved. It is impossible to say more of this work here than that it is a very valuable contribution to general dynamical geology and the writer feels from his own experience that it will be of distinct service in solving many problems in connection with the occurrence of igneous rock-masses. The paper is illustrated with many diagrams, sketches, photo-engravings and contains a geological map. L. V. P. 5. A Petrographical sketch of Aegina and Methana; by H. S. WASHINGTON. Journal of Geology (Chicago), vol. ii, No. 8, vol. iii, Nos. 1 and 2, 1895.-This paper contains a careful and detailed study of the igneous rocks occurring in a limited area in Greece. It is accompanied by a geological map and possesses many facts of interest to petrologists. It is especially valuable in being accompanied by a large number of excellent analyses which enable the author to discuss the region from a broad standpoint of general petrology. It thus possesses distinct features of general interest beyond those of petrographic detail. L. V. P. 6. Geologische und geographische Experimente ausgeführt mit Unterstützung der K. Akademie der Wissenschaften von ED. REYER. III, Heft, Rupturen. IV, Methoden und Apparate. 32 pp. with 12 plates. Leipzig, 1894 (Wm. Engelmann).-The author continues in this small volume his earlier investigations and gives interesting results and conclusions drawn from them in regard to ruptures of various kinds, volcanic cracks, faulting and so on. The methods and apparatus are briefly but clearly described, the text being illustrated by numerous figures. 7. On a new locality for Xenotime, Monazite, etc., on Manhattan Island; by WILLIAM NIVEN. (Communicated.)-The xenotime crystal measured by Mr. H. S. Washington and announced by Mr. W. E. Hidden in this Journal for November, 1888 (vol. xxxvi) was found by the writer in a vacant lot at 175th street near 10th avenue, New York City, amongst loose blocks of mica schist and gneiss which had been dumped there some years before: the exact locality, therefore, remained in doubt. Recently, however, while prospecting in the extensive excavations for the new speedway on the Harlem River I found a number of crystals of this interesting mineral in place, also monazite, titanite, epidote, beryl, menaccanite and others. Prof. A. C. Gill of Cornell University has determined the xenotime by measurement of the angles, finding that they agree to within 1' with those given by Mr. Washington in Mr. Hidden's article, one crystal showing a very narrow pyramid of the second order Pa (101) in addition to the forms P(111), a P(110) and 3P3(311) which were identified by Mr. Washington. This face P (101) is new to New York xenotime, although observed elsewhere. The most interesting crystal showed an abnormal development along the vertical axis producing a prismatic form like that common in zircon, while in close proximity to it was a crystal of the ordinary habit. The monazites were usually found in close association with the xenotimes. All were well defined crystals, and one was exactly of the habit shown in figure 2, page 750, Dana's System of Mineralogy, sixth edition, as occurring at Watertown, Conn. The titanites have a remarkable resemblance to those from Tyrol and were usually about 12mm in size, one crystal measured fully 40mm and some fragments were transparent. A surface of the schist over 20cm by 28cm in size showed more than 40 yellowish green crystals. The xenotimes and monazites were mostly embedded in oligoclase near a coarse granite vein at 185th street and Harlem River and were associated with menaccanite, while the titanite and epidote occur in a chloritic mica schist at 167th street and Harlem River. My thanks are due to Prof. A. C. Gill for identifying and measuring the crystals. 8. Brief notices of some recently described minerals.-LAWSONITE, named after Prof. A. C. Lawson, is a new rock-forming mineral described by F. Leslie Ransome, from the crystalline schist of the Tiburon Peninsula, Marin County, California; also occurring in larger crystals embedded in a micaceous mineral determined as margarite in veins in the schist. It forms crystals of prismatic habit belonging to the orthorhombic system: prismatic angle 67° 16'; cleavage perfect parallel to b and less so parallel to c; crystals colorless to pale blue; hardness about 8; specific gravity 3.084. An analysis gave: SiO Al2O3 28.88 18.26 Fe,03 CaO MgO Na,O H20 38.10 2 10 This yields the formula H,Ca Al, Si,O,,; a possible relation to carpholite is suggested.-Bull. Dept. Geol., Univ. California, vol. i, No. 10. ELPIDITE.—A silicate of zirconium and sodium from Igaliko, Greenland, described by G. Lindström. It occurs in fine fibrous forms with silky luster; the color varies from white to yellowish white and light brick-colored; hardness about that of quartz; specific gravity 2:524 to 2.594. Analysis gave: SiO, ZrO2 Na2O K20 FeO CaO 59:44 20:48 10:41 0.13 0.14 0.17 HO(100°) H2O(ign.) Cl 3.89 5.72 0.15 CuO, TiO2 tr=100.53 The calculated formula is Na,O.ZrO,.6SiO,.3H,O.- Geol. För Förh., xvi, 330, 1894. LOSSENITE.-A new arsenate from Laurium, Greece. Described by L. Milch. It occurs in small red-brown crystals referred to the orthorhombic system and resembling scorodite in form. Analysis by Auerbach gave (after deducing gangue) AS205 SO3 Fe2O3 Pbo 34.33 3.84 35.45 10.91 H2O (comb.) 3.84 12.12 100-49 For this the complex formula 2PbSO ̧ . 6(FeOH), As2O̟.. 27H ̧O is calculated. Zeitschr. Kryst; xxiv, 100, 1894. DIETZEITE.—A name proposed by Osann for the iodate and chromate of calcium occurring, as described by Dietze, with the calcium iodate, lautarite, at the Pampa del Toro, Chili (Zeitschr. Kryst., xix, 447, 1891 and Dana, Syst. Min., 1892, p. 1040). Osann describes monoclinic crystals. URBANITE.-A name proposed by Sjögren for a so-called ironschefferite analyzed by Mauzelius, from Långban, Sweden. Igelström later calls it lindesite and claims priority on insufficient grounds. Geol. För. Förh., xiv, 251, 1892; Zeitschr. Kryst., xxiii, 590, 1894. - MINERVITE-A phosphate of aluminum occurring in seams in a calcium phosphate, a formation in the "Grotte de Minerve" on the shores of the river Cesse, Dept. Aude, France. The formula PO. ALO, 7H,O is deduced for it described by A. Gautier.— Bull. Soc. Min., xvii, 132, 1894. 2 WEBNERITE. An argentiferous variety of zinckenite described by Stelzner from Oruro, Bolivia. It has been found in massive form only. An analysis by P. J. Mann gave: This leads to the formula PbS. Sb,S, in which silver replaces lead, the ratio for Pb: Ag being about 5: 2.-Zeitschr. Kryst., xxiv, 125, 1894. 9. Note on a Garnet from California; by F. W. CLARKE. (Communicated.)-In March, 1895, I received from W. J. Knowlton of Boston, for examination, a waterworn pebble found at Eltoro, 40 miles south of Los Angeles, California. The specimen weighed 525 grams, was very compact, quite highly polished, and pale apple-green in color. In fact, it was supposed to be jade; and, so far as appearance was concerned, it fully justified the supposition. Believing it to be either nephrite or jadeite, I had an analysis of it made by Mr. George Steiger, in the U. S. Geological Survey laboratory, which showed it to be really grossularite garnet. The data are as follows: Specific gravity, 3:485. The loss on ignition includes a trace of carbonic acid. On treating 0.2 gram of the powdered mineral with hydrochloric acid, evaporating to dryness, and then redissolving, about 16 per cent of alumina and 20 per cent of lime went into solution. In this respect the specimen is therefore somewhat unusual. But as a garnet simulating jade it is certainly interesting. 10. Physikalische Krystallographie und Einleitung in die krystallographische Kenntniss der wichtigeren Substanzen von PAUL GROTH. Dritte vollständig neu bearbeitete Auflage. III Abtheilung, pp. i-xvi, 529–783, Leipzig, 1895 (Wm. Engelmann).―This third part completes the revised edition of Professor Groth's Physical Crystallography, already noticed on p. 74 of the last volume. It is devoted to a discussion of the methods of calculation applied to crystals, and to the apparatus and methods of investigation in the departments of Crystallography and Physical Mineralogy. To those who are acquainted with the earlier editions of the author's work, it is unnecessary to say that these topics are treated with all desirable completeness and clearness and that the most recent and important improvements in instruments are fully described. III. BOTANY. 1. Die natürlichen Pflanzenfamilien.-Recent numbers of this serial work bear the single name of Professor Engler, of Berlin. After the loss of Eichler, its founder, and of Prantl, a co-editor, the entire conduct of editing was entrusted to Professor Engler. He has not introduced any new elements into the work, and the collaborators pursue their specialties on the same lines as at first. The present installments contain Hippocastanacea, by F. PAx; Sapindacea, by L. RADLKOFER; Sabiacea, by O. WARBURG; Tamaicace, by F. NIEDENZU; Cistaceae, by K. REICHE; Bixacea, Winteranacea, (Canellacea,) by O. WARBURG; Koeberliniaceae, by A. ENGLER; Violacea, by K. REICHE and P. TAUBERT. From this can be seen the wide range of contributions, and some idea can be gained from this of the immense difficulty of editorial supervision, in keeping everything within due limits space and in proper proportion. Aside from the annoyance of having the installments appear in different parts of the field, a fact inseparable from the mode of preparation, the work has progressed to the satisfaction of subscribers. The promises of the publishers have been more than kept, especially as regards excellence and copiousness of the engravings and the high order of typographical execution. The English translation will be received with a hearty welcome. of G. L. G. 2. Familiar Flowers of Field and Garden, by F. SCHUYLER MATHEWS. New York, 1895. (D. Appleton & Co.)-The increasing number of popular works on various subjects in Natural History may be taken as an expression of an increasing interest in some phases of Zoology and Botany. Even the wretched text and misleading illustrations of a botanical work published during the past year, as a premium for a syndicate of newspapers, may be perhaps interpreted as an indication of a desire on the part of the public to gain information in regard to plants. Happily some of the recent popular works on Botany are of an entirely different character, being generally trustworthy and in good taste, although they may be rather unsatisfying on account of the limited scope. Among such useful works may be mentioned Mrs. Dana's work, in which color is made to serve as an aid to the beginner in studying plants, and also the book which we have placed at the head of this notice. Mr. Mathews is an artist and has studied the plants around him chiefly from the point of view of an intelligent lover of form and color. His sketches, about two hundred, are spirited and faithful. The descriptions are sufficiently detailed to be helpful to one who is just entering on the study of flowers, and no serious mistakes are observable in any part of the book. The little treatise is attractively printed and is bound in flexible covers, of a size fitting it for the pocket. G. L. G. |