been uncovered, in which has appeared over a tract of 50,000 square meters a luxuriant growth of Glaucium, which is characterized as a new species under the name of G. serpieri, and is unknown elsewhere at the present time. It would appear from the indications that the seeds of this plant must have remained alive during the interval of 1500 or 2000 years which have elapsed since the mines were last worked. -13 A, March 29, 1875, 295.

STIMULATING ACTION OF CAMPHOR ON PLANTS.

Dr. Vogel, of Munich, has repeated the experiments made by others on the stimulating action of camphor upon the growth of plants. He concludes that, except in a few cases, we possess in camphor a stimulant capable of greatly increasing the luxuriance and rapidity of the growth of plants. Thus, when branches of seringa in flower were introduced into camphorated water, the drooping of the plant was entirely overcome, some blossoms being even developed under these circumstances. The seeds of Lopidium sativum, after having been kept dry for three years, were watered with camphorated water, and germinated with remarkable quickness; while the seeds of Raphanus sativus major, which had been dried for five years, and had refused to germinate in the garden, when treated with camphorated water germinated in four days. Similar interesting results have been obtained with other seeds. Some experiments made with the essence of terebinthine have shown that, while like camphor favoring the germinating process, the former arrests the ulterior development of the plant.-Bull. Hebd., XVI.,

46.

DARWIN ON INSECTIVOROUS PLANTS.

Mr. Darwin's new work on insectivorous plants has been a great success, 2250 copies of the English edition having been sold in a very short time. The most interesting and novel point which he brings out is the existence in Drosera, Dionæa, and some other plants which come under this designation, of an actual digestive fluid, which in the case of Drosera becomes acid only when the secreting glands are excited by the presence of nitrogenous matter, a substance being formed apparently closely analogous to the pepsin

contained in the gastric juice of animals. The excessively minute quantities of nitrogenous substance which cause inflection of a gland of Drosera are very astonishing—in the case of carbonate of ammonia about a twenty millionth of a grain.

INFLUENCE OF AMMONIA ON THE COLORS OF FLOWERS.

The Journal of the Central Horticultural Society of France gives some interesting details of the alterations which the natural colors of flowers are subjected to under the influence of ammonia. If we expose flowers originally of a violet hue to the fumes disengaged by a cigar, we see these flowers take a green tint more pronounced than was their proper color. This change is due to the ammonia in the tobacco smoke. Starting with this idea, the Italian Professor Gabben has made a series of experiments having in view the changes that ammonia brings about in the colors of different flowers. He simply made use of a plate containing a certain quantity of a solution of ammonia known commonly as volatile alkali. He shows that, under the influence of ammonia, blue, violet, and purple flowers become a beautiful green, red and carmine grow black, and white flowers turn yellow. The changes of color which are most singular are those shown by the flowers which have many different tints, out of which the red lines become green, the white yellow, etc. A remarkable example of this is seen in the fuchsias having white and red flowers, and which by the action of ammoniacal vapors become yellow, blue, and green. When the flowers have been subjected to the changes that color them, they will, if plunged in pure water, retain their new colors for many hours, after which they return to their primitive shade. Another interesting observation, due to Gabben, is that the flowers of the aster, which are naturally inodorous, acquire an agreeable aromatic perfume under the influence of ammonia. The flowers of these same asters, whose natural color is violet, become red when washed with diluted nitric acid.-1 B, XV., 42.

HOLLYHOCK FUNGUS.

The hollyhocks of Europe are threatened with destruction by the rapid development of a fungus known as Puc

cinia malvacearum, and probably imported from Chili, where it was discovered on Althaea officinalis. It was first observed in the neighborhood of Bordeaux, France, in April, 1873, on Malva sylvestris, and extended rapidly to other plants of the same order in the botanic gardens of that town. It appeared in Germany in October, having been found in England in the preceding summer.-12 A, April 16, 1874,

470.

PROPOSED WORK ON AMERICAN FOREST TREES.

Dr. F. B. Hough, of Lowville, New York, well known in connection with his efforts looking toward the protecting of American forests from destruction, proposes, should he succeed in obtaining at least two hundred subscriptions, to publish a work which will be of much interest to botanists, microscopists, and workers in wood. This will consist of actual sections of two hundred species of American woods, properly mounted for examination under the microscope, and suitably labeled, to be accompanied by text containing descriptions of the species represented, of their qualities and uses, with other statistical information. The whole will form three small quarto volumes, and the specimens will be prepared by Professor Nördlinger, of Hohenheim, who has already been connected with similar publications relating to the forest trees of Europe.

A NEW WORK BY MR. DARWIN.

Mr. Darwin has lately published in England, under the title of "The Movements and Habits of Climbing Plants," a reprint of his paper on this subject printed some years ago in the Journal of the Linnæan Society of London, which first attracted public attention to the remarkable phenomena connected with the rotation of climbing stems and tendrils. A good deal of fresh matter is also inserted. Mr. Darwin's work on "Insectivorous Plants" has met with a large sale, being already in a third edition. Professor E. Morren, of Liege, has published in the Bulletin de l'Académie Royale de Belgique a record of a series of experiments which, while they abundantly confirm the insecticidal powers of the leaves of Drosera and Pinguicula, lead him to doubt the power of absorption and digestion assigned to them by Mr.

Darwin. MM. Reess and Will, on the other hand, in the Botanische Zeitung, abundantly confirm Mr. Darwin's results in the case of Dionaea and Drosera, as is also the case with two independent series of observations carried on in England by Dr. Lawson Tait and Mr. J. W. Clark. The former gentleman claims to have established the absorptive power of the leaves of Drosera by planting in perfectly pure silver sand plants from which the roots had been entirely removed, and feeding them with extract of beef and phosphate of ammonia; the latter by feeding the leaves with bodies of flies soaked in a solution of citrate of lithium, and then finding the lithium in other parts of the plant by means of the spectroscope.

FERTILIZATION OF A FERN.

Mr. H. H. Babcock has lately communicated an interesting fact in regard to a well-known fern, the Aspidium acrostichoides. In this plant, at the time of maturing of the spores, the elastic band of each theca slowly straightens out, carrying the spores in a mass at its tip. After straightening and bending back as far as possible, it gives a sudden forward spring, projecting the spores in a shower. It then gradually resumes its original position, and then the theca presents the appearance of having simply been ruptured to allow the spores to fall out.

NEW WORK ON MEDICINAL PLANTS.

A new work has been commenced in London, under the title of "Medicinal Plants," to contain colored plates included in the pharmacopoeia of Great Britain, India, and the United States, together with descriptions of plants, their nomenclature, geographical distribution, etc., and an account of their properties and uses.

L. AGRICULTURE AND RURAL ECONOMY.

NOXIOUS EXHALATIONS FROM THE MEADOW-SAFFRON.

Isidore Pierre communicates to the Paris Academy an interesting fact in regard to certain exhalations from the flower of the Colchicum autumnale, or meadow-saffron. In passing through a garden where these plants were in full bloom he accidentally held his hand near the flower, and found, after a few seconds, that his fingers had changed color, and assumed a yellowish-green tint, similar to that of the decomposing human subject. In a short time, however, the skin resumed its natural color. The precise character of this emanation Pierre was unable to determine. It could not be any solid substance, as it would have been much more persistent. He thinks, therefore, it is some extremely volatile liquid, which he proposes to investigate hereafter. He is convinced, also, that exposure to it produced certain uncomfortable sensations both in his hand and his mouth, calling to mind the toxical effects of the meadow-saffron, which under certain circumstances, especially when fresh, is highly poisonous.6 B, September 14, 1874, 635.

VARIOUS INSECT-POWDERS.

The very great extent to which the various insect-powders now before the world are used for the destruction of noxious insects is well understood at the present time, the apparent quackery of the recommendations of the insect-powders being now well substantiated by abundant experience. Although insect-powders have been in use from time immemorial in China, Tartary, Thibet, etc., especially in enabling the herdsmen of the steppes to exist in company with the countless myriads of gnats and mosquitoes (for which purpose the substance is burned inside of the tent), it was not until 1846 that Zachrel, a Tiflis merchant, first introduced it for sale. in Vienna, under the name of "Persian Insect-Powder." This was originally derived from two plants, the Pyrethrum carneum and P. roseum, both growing wild in the Caucasus, and largely cultivated there. Since that time the manufact