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the detailed description of the individual specimens in the museum, this little book contains some remarks upon the different kinds of rocks of Victoria and their relations, which give it something more than a local interest. A considerable number of analyses are given, especially for the igneous rocks.

10. Geology of Illinois.— The last volume of the series of reports connected with the Geological survey of Illinois under Mr. Worthen is now in the binder's hands.

11. Geological map of the United States and Canada.In a few days, a Geological chart of the United States (east of the 104th meridian) and Canada, by Prof. F. H. BRADLEY, will be on sale by Messrs. Ivison, Blakeman, Taylor & Co., 138 and 140 Grand street, New York, the publishers of Professor Dana's works on Geology. Its size is 24 inches by 16. It contains all the detail and accuracy possible on a chart of this size in the present state of the science. The geological areas are well distinguished by a judicious system of lining, instead of by colors, and hence the chart will be afforded, as we understand, at the low rate of one dollar each. It should be in the hands of all students in geology, and is absolutely indispensable to every teacher.

12. Einleitung in die Krystallberechnung; von Prof. Carl Klein, Erste Abtheilung. 208 pp. 8vo. Stuttgart, 1875.-Prof. Klein develops the subject of Crystallography from the standpoint of Quenstedt, according to whom the relations of the planes of a crystal are shown by the lines in which they are projected upon a given plane of projection. He does not confine himself to the somewhat unwieldy formulas of Quenstedt, however, but makes all calculations of axial relations and parameters by means of spherical triangles in the manner employed by von Kobell. The author has worked out with much care and completeness the solutions of the various problems which arise, and accompanies each with an example performed in full, so that the student cannot fail to comprehend the method.

E. S. D. 13. On Troilite : by Dr. J. LAWRENCE SMITH.-A paper on troilite by Dr. Smith was read before the French Academy of Sciences on the 22d of November last. The author shows by new and careful analyses that troilite, or the sulphide of iron of meteorites, has the composition he has before obtained for it, represented by the formula Fes, and not that of pyrrhotite (FeSs) to which species it is referred by M. Saint Meunier in a communication to the Academy of March, 1874. He observes that the specific gravity of troilite, 4.813, also separates it from pyrrhotite, a selected specimen of the latter affording him only 4.642. As this meteoric sulphide is found imbedded in a mass of iron, “the natural supposition is that the sulphur would be saturated with the iron." Hence, he adds, "troilite like schreibersite, is exclusively a celestial mineral.

Rectification of the Geological map of Michigan, embracing observations on the Drift of the State; by Alexander Winchell. 17 pp. 8vo. Salem, 1875. From Proc. Amer. Assoc. for 1875.

III. BOTANY AND ZOOLOGY. 1. Karl Koch, Vorlesungen über Dendrologie. Lectures on Dendrology, delivered in Berlin in the winter semester of 1874–75. Stuttgart, F. Enke, 1875, pp. 408, 8v0.—These are the notes of a course of popular lectures by Prof. Koch, on a subject in which he is thoroughly at home. They must have been delightful to hear, as they are pleasant to read, and are full of interesting matter. It is only the first course of a series which is to be continued this winter. The first division, of seven lectures, is a history of landscape gardens and gardening. The second division, of as many more, treats of the structure, growth, and life of trees, of the influence of woods upon mankind, and as regulators of temperature and atmospherical changes. The third division, in four lectures, treats of Coniferous trees,-all in a popular way. Prof. Koch insists that the two willows confounded as forms of the Weeping Willow, are neither of them Persian or Assyrian, except by immigration, but vatives of a farther east, i, e., of China and Japan. One of them may have reached Western Asia, however, early enough to have been collected by Tournefort, and so to excuse the error fixed by Linnæus by his name of S. BabyLonica. But even the last volume of DeCandolle's Prodromus does not rectify it. Notwithstanding Prof. Koch's correction and elucidation, it is likely that popular books and the popular belief will continue to associate the Weeping Willow with the River of Babylon and the hanging barps of the weeping Israel. ites, although the tree of the Psalm most likely was a Poplar. We believe it was Ker Porter who remarked that willows were to be found along the river, but only as low shrubs: upon these nothing larger than a comparatively modern musical instrument associated with the name and nation could well be hung. When the course is completed we shall look for an English edition of these lectures upon tree-lore.

A. G. *2. Insectivorous Plants ; by CHARLES Darwin. With illustrations. London: Murray. New York: D. Appleton & Co.This long expected work appeared last' autumn, was immediately reprinted by the American publishers, and before this time has been so widely read that no detailed account of it is at all necessary. Its main topic is Drosera or Sundew, upon which the vast number and diversity of the observations and experiments—at once simple, sagacious, and telling-which it records, are about as wonderful as the results. As to the latter, it is established berond question that the common Sundews are efficient fly-catchers; that the stalked glands, or tentacles, as Mr. Darwin terms them, are sensitive and turn inward or even in other required directions in response to irritation; that they equally respond and move in obedience to a stimulus propagated from a distance through other tentacles and across the whole width of the leaf; that the sensitiveness belongs only to the glands and tips of the tentacles, but is propagated thence down their stalks and across the blade of the leaf through the cellular tissues; that they accurately and delicately discriminate animal or other nitrogenous matter from anything else; that the glands absorb such matter; that when excited by contact, or by the absorption of nitrogenous matter by the viscid enveloping liquid, an acid secretion is poured out and a ferment analogous to pepsin, the two together dissolving animal matter; so that the office and action of these glands are truly analogous to those of the glands of the stomach of animals. Finally that animal or nitrogenous matter, thus absorbed and digested in the glands, is taken in, and conveyed from cell to cell through the tentacles into the body of the leaf, was made evident by ocular inspection of the singular changes in the protoplasm they contain. So particularly have the investigations been made and so conscientiously recorded, that the account of those relating to one species of Sundew, Drosera rotundifolia, fills 277 pages of the English edition, or more than half of the book. After all it ends with the remark: “and we see how little has been made out in comparison with what remains unexplained and unknown.” The briefer examination of six other Sundews follows, some of them equally and others less efficient fly-catchers and feeders.

Dionica is next treated, but with less detail. Indeed, except as to the particular nature of the secreted digesting fluid, there is little in this chapter that had not been made out or already become familiar here. That the secretion has digestive powers, and that it is re-absorbed, along with whatever has been digested, is now proved beyond reasonable doubt. That the motor impulse is conveyed through the ce!lular parenchyma, and not through the vascular bundles, or spiral vessels, and that the latter do not originate the secretion, as Rees and Wills in a recent paper seem to suppose they must, appears to be shown by the facts, and was antecedently probable. 6 The wonderful discovery made by Dr. Burdon Sanderson is now aniversally known: namely, that there exists a normal electrical current in the blade and footstalk, and that when the leaves are irritated the current is disturbed in the same manner as takes place during the contraction of the muscle of an animal.” The conclusion here needs to be checked by parallel experiments, to see whether the same reversion of current does not take place whenever a part of any leaf or green shoot is forcibly bent upon itself.

Aldrovanda vesiculosa, of the Drosera family, “may be called a miniature aquatic Dionæa ;" for, as discovered by Stein in 1873, “ the bilobed leaves open under a sufficiently high temperature, and when touched suddenly close.” Being submerged, their prey is confined to minute aquatic animals. For want of proper material and opportunity, Mr. Darwin was able to follow up only for a little way the observations of Stein and Cohn,-enough, however, to show that it also captures and consumes animals, but perhaps avails itself of the nitrogenous matter only when passing into decay.

Drosophyllum, a rare representative of the order, confined to Portugal and Morocco, grows on the sides of dry hills near Oporto; so that, as to station, it is the very counterpart of Aldrovanda. Its leaves are long and slender, in the manner of our Drosera filifirinis, and are covered with much larger glands. To these flies adhere in vast numbers. “ The latter fact is well known to the villagers, who call the plant the 'fly catcher,' and hang it up in their cottages for this purpose.” Mr. Darwin found the glands incapable of movement, and their behavior in some other respects differs from that of Drosera; but they equally secrete a digestive juice. Insects usually drag off this secretion instead of being fixed on the glands by it; but their fate is no better; for as the poor animal crawls on and these viscid drops bedaub it on all sides, it sinks down at length exhausted or dead, and rests on a still more numerous set of small sessile glands which thickly cover the whole surface of the leaf. These were till then dry and ipert, but as soon as auimal matter thus comes in contact with them, they also secrete a digestive juice, which, as Mr. Darwin demonstrated, has the power of dissolving bits of coagulated albumen, cartilage, or meat, with even greater readiness than that of Droseru.

Vr. Darwin next records various observations and experiments upon more ordinary glandular bairs of several plants. To certain Saxifrages his attention was naturally called, on account of the presumed relationship of Droseraceve to this genus. He declares that “their glands absorb matter from an infusion of raw meat, from solutions of nitrate and carbonate of ammonia, and apparently from decayed insects. To such plants the vast number of little insects caught may not be useless, as they may be to many other plants (tobacco, for instance) with sticky glands, in which Mr. Darwin could detect no power of absorption. The prevalent idea, that glandular hairs in general serve merely as secretingo" excreting organs, and are of small or no account to the plany must now be reconsidered. Those of the common Chinese Primrose (Primula Sinensis) although indifferent to animal infusions, were found to absorb quickly both the solution and vapor of carbonate of ammonia. Now, as rain-water contains a small percentage of ammonia, and the atmosphere a minute quantity of the carbonate or nitrate, and as a moderate-sized plant of this primrose was ascertained, (by estimate from a count on small measured surfaces by Mr. Francis Darwin) to bear between 2 to 3 millions of these glands, it begins to dawn upon us that these multitudinous organs are neither mere excrescences nor outlets, nor in any just sense insignificant.

Mr. Darwin next investigates the densely crowded short glandular hairs, with their secretions, which form the buttery surface of the face of the leaves of Pinguicula, the Butterwort. He finds that the leaves of the common Butterwort have great numbers of small insects adhering to them, as also grains of pollen, small seeds, &c.; that most substances so lodged or placed, if yielding soluble matter to the glands, excite them to increased secretion; but that if non-nitrogenous the viscid fluid poured out is not at all acid, while if nitrogenous it invariably has an acid reaction and is more copious; that in this state it will quickly dissolve the muscles of insects, meat, cartillage, fibrin, curds of milk, &c.; that when the surface of a plane leaf is fed, by placing upon it a row of flies along one margin, this margin, but not the other, folds over within twenty hours to envelope them; and when placed on a medial line, a little below the apex, both margins incurve. He concludes “ that Pinguicula vulgaris, with its small roots, is not only supported to a large extent by the extraordinary number of insects which it habitually captures, but likewise draws some nourishment from the pollen, leaves, and seeds of other plants, which often adhere to its leaves. It is therefore partly a vegetable as well as an animal feeder.” The leaves in one or two other species were found capable of greater and more enduring inflection, and the glands excitable to increased secretion even by bodies not yielding soluble nitrogenous matter.

The aquatic type of this family is Utricularia; and the bladderbearing species of this genus are to Pinguicula nearly what Aldrovanda is to Dionæa and Drosera—the bladders imprisoning minute aquatic animals, by a mechanism almost as ingenious as that of Dionaea itself. Observations of the same kind were made in this country by Mrs. Treat, of Vineland, New Jersey, before Mr. Darwin's investigations were made known. These submerged aquatic stomachs, ever deluged with water, apparently do not really digest their captures, but merely absorb the products of their decay.

The same must in all probability be said of such Pitcher plants as Sarracenia and Darlingtonia, which Mr. Darwiu merely alludes to at the close of his volume but does not treat of. Nepenthes, however, according to Dr. Hooker's investigations, has attained a higher dignity, and converted its pitcher into a stomach. This parallelism, and this higher and lower mode of appropriating organic products by each of the three well-marked carnivorous families of plants, are highly suggestive.

In concluding this notice of a book for which we have no room to do justice-but which is sure to be in the hands of many interested readers—there is somewhat to be said in regard to the discovery of the lure in some of our Sarracenias. We have by degrees to discover our discoverers. In this Journal, only so far back as the number for August, 1873, is a notice of the discovery of a sweet secretion at the orifice of the pitcher of Sarracenia flava, by Mr. B. F. Grady, of Clinton, North Carolina (in the article by an oversight called “Mr. Hill"), which effectively lures flies to their destruction. This statement, made in a letter, had been for several months in our hands, awaiting the opportunity of confirmation, when an allusion to the same thing appeared in the English edition of LeMaout and Decaisne's System of Botany, without reference to any source, and on inquiry we learned that the authority

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