moved was thrown outside of the building. From these the species has been disseminated. It is known as the Acanthospermum xanthoides.-Bull. Torrey Botan. Club, May, 1876.

INVESTIGATIONS ON AMERICAN GOOSEBERRIES.

Professor Gray, in an article in the American Naturalist for May, in reference to the unsatisfactory condition of our knowledge in regard to the American wild gooseberry, invites botanists throughout the country to furnish information and specimens by which the difficulties may be cleared up. The species so far known to botanists are eleven in number, but the history of several of these is very indefinite.—Bulletin Torrey Botan. Club, May, 1876.

EXHIBITION BY THE AGRICULTURAL DEPARTMENT OF AMERICAN WOODS AT THE CENTENNIAL

One of the most interesting features of the government exhibition at the Centennial is the collection of sections of forest trees displayed by the Agricultural Department, made under the direction of Dr. George Vasey, botanist of the department. This includes nearly 400 species and varieties of native North American trees, gathered directly for this occasion by twelve collectors in various parts of the Union. They embrace 50 species of sub-tropical trees of Southern Florida, including five that are new to our flora, and obtained by Dr. A. W. Chapman; 25 species from Texas, one of them believed to be new; 30 from Southern California and Arizona, embracing the tree yuccas and a recently known palm; 50 species from the Pacific slope of California; and 10 or 12 of the peculiar forms of Oregon. Among the 30 species from the Sierra Nevada Mountains are large sections of some of the noblest conifers of the world, such as the sugar-pine, the Douglas spruce, the silver-fir, and others.

The Rocky Mountains in Colorado and Utah furnish about 30 species; Illinois and the Western States, 50; Vermont, 20; and Virginia about 50, most of the latter being from the Mount Vernon estate, near Washington.

From the Southern States, exclusive of South Florida, there are about 90 species, one of them believed to be new. There are 30 species of oaks, 30 of pines, 16 of spruce, and 20 of other conifers. There is one extremely interesting group,

consisting of the tree palmettos, palms, and yuccas of the United States, embracing the Sabal palmetto from Florida, one palm from California, two yuccas from Florida, and three from Texas, Arizona, and California.

The sections referred to are not mere hand specimens, such as are usually found in collections, but in many cases they are two or three feet long, and of the full trunk whenever this is not too large for exhibition.

LIVING TREES AT THE CENTENNIAL.

Among the more interesting exhibitions at the Centennial is a collection of living woody plants exhibited by Mr. Thomas Meehan, of Germantown. These plants were all grown for a certain time in boxes, with special reference to their transplantation, and were inserted in the ground with balls of earth around them, so that they are now growing very vigorously. As this collection is for sale after the close of the Exhibition, it offers an excellent opportunity to any establishment in the United States that wishes to secure a collection of American plants of extraordinary completeness.-D. Ill. Gewerbezeitung, XXIII., 1876.

CHANGES OF COLORATION IN FLOWERS BY ARTIFICIAL MEANS.

The French Journal of Horticulture, in an article upon the changes of coloration which certain natural flowers undergo, remarks that if violet flowers are exposed to the smoke from a burning cigar they change color and assume a tint of green, which is decided in proportion to the brilliancy of their orig inal color. This is due to the ammonia in the smoke. Starting out with this fact, Professor Gobba has made a series of experiments for the purpose of determining the changes which ammonia produces in the colors of different flowers. For this purpose he merely makes use of a dish in which is poured a small quantity of common aqua ammonia. Over this he places a funnel, in the tube of which are inserted the flowers to be experimented upon. In this way he has shown that blue, violet, and purple flowers change to a beautiful green; deep red carmine flowers to black, white to yellow, etc. These changes are most striking where the flowers have sev eral different tints, in which the red lines are turned green, the white yellow, etc. An interesting example is that of the

fuchsias, with white and red flowers, which, in consequence of the ammonia vapor, become yellow, blue, and green. If, when these changes have taken place, the flowers are immersed in pure water, they preserve their new colors for several hours, after which they gradually resume their original. tints. Another observation due to Mr. Gobba is that the flowers of the asters, which are naturally inodorous, acquire a very agreeable perfume under the influence of ammonia. The flowers of the violet asters also become red when they are moistened with a diluted solution of nitric acid. Again, these same flowers, if exposed in an open box to the vapor of hydrochloric acid, become after some hours of a beautiful carmine red, which they preserve after being dried in the dark, if kept in a dry, dark place.-1 B, April 4, 1876, 422.

PRESERVATION OF CUT FLOWERS AND BOUQUETS.

A German journal recommends for the preservation almost indefinitely of cut flowers, singly or in bouquets, to dip them in a solution of pure albumen, and, after allowing them to become perfectly dry, to repeat the operation several times, each time with fresh albumen.-10 C, May 1, 1876, 79.

VARIETIES OF INDIA RUBBER.

A recent writer enumerates the following varieties of India rubber as known in commerce: 1, Ceara rubber; 2, Para rubber; 3, Quisembo balls from Sierra Leone; 4, African knots in small irregular quadrangular pieces about an inch square; 5, Mozambique rubber; 6, African niggers in small round lumps about two inches in diameter; 7, Madagascar rubber; 8, Carthagena rubber; 9, Borneo rubber; 10, Rangoon rubber; 11, African rubber; and, 12, Guayaquil rubber from Ecuador.-D. Ill. Gewerbezeitung, XXIII., 1876.

A NEW DRYING OIL.

The Elaococca Vernicia, or Tong-Yeou, a tree growing in China and Cochin-China, produces abundantly a fruit consisting of a capsule filled with grains rich in oil. This oil is easily extracted by pressure, has a density of 0.9362, and possesses a variety of curious properties. According to Cloez, who has lately submitted it to thorough investigation, it dries more rapidly than any other known oil, a coating of it ap

plied to glass or clean metallic surfaces becoming dry in a very few hours. An attempt will probably be made to acclimatize the plant in Algeria, with a view toward rendering it useful in the arts and introducing it into commerce. One of the most remarkable facts connected with the oil is its power of solidifying under the action of light and out of contact with the air. Heated in the air it also becomes solid, this change being, however, a chemical one due to oxidation. -6 B, September 13, 1875.

THE HEATH IN AMERICA.

It has been a generally received impression that North America, in distinction from Europe, is without any species of heath or heather, a few specimens of the Calluna vulgaris detected in Newfoundland having been considered as introduced rather than as indigenous. Great, therefore, was the gratification of sentimentalists at the discovery of this plant in Tewksbury, Massachusetts. Afterward the same plant was discovered in Nova Scotia and Cape Breton, and subsequently on Cape Elizabeth, near Portland. Dr. Gray now announces in the American Naturalist the discovery of a second station in Massachusetts, to the west of Andover, about five miles north of the Tewksbury station. A signal feature in this connection is the vicinity of a glacial moraine which traverses the district.-5 D, August, 1876, 490.

EFFECT OF SOLUTIONS ON A GROWING VINE.

Baudrimont has been continuing his experiments upon the influence upon the branches of a growing vine of immersion in water containing various substances in solution, and has obtained some rather remarkable results by various poisonous agencies, some appearing actually to increase the vigor of growth of the vine and prolong its existence, as in the case of chloride of potassium; while others cause the plant to wither, as in creosote and carbolic acid. Bromide and iodide of potassium seem to act in the same manner as chloride of potassium. Chloral hydrate exercises a very poisonous influence, destroying the branch vine in three days, the effect differing from that of carbolic acid. One of the most curious phenomena is that which is exhibited in the fall of the leaves. In some instances the petiole becomes detached at the point

where it is inserted in the branch. This takes place in case of most substances, such as bichloride of mercury, and chloride, bromide, and iodide of potassium. In other cases it is the limb which separates from the extremity of the petiole. This occurs with ordinary water, and the nitrates of ammonia, potash, and soda. In one single instance both forms of separation have been observed, under the influence of the same substance. Sometimes, again, the branch dies while the leaves continue to adhere to it. This is the case after the use of hydrocyanic acid and the essence of turpentine. Chloride of potassium acts as an invigorating and preserving agent, quite exceptional in its character. A current of ammonia allows the branch to preserve its freshness for eight days, after which it withers.-1 B, December 20, 1874, 189.

PLANTS OF NEW GUINEA,

The Gardener's Chronicle states that letters received from Ternate mention the fact that Dr. Beccari has discovered on Mount Arfok, in New Guinea, quite a number of new species of plants of well-known genera, belonging to very different portions of the globe. Among these are Araucaria, species of Vaccinium, Rhododendron, Podocarpus, etc.

SECRETION OF DROSERA.

The alleged insectivorous habits of certain plants, such as Drosera and Dionaa, have attracted attention to the question of the composition of the viscid substance secreted by the glands on the leaves of species belonging to the former of these genera. The properties of this substance are evidently closely analogous to those of the pepsin which is the ferment secreted in the human stomach, and it is said even to give off the odor of pepsin on treating with sulphuric acid; but the quantity in which it has hitherto been obtained is too small to admit of accurate analysis. Professor Frankland, of London, obtained results which convinced him that the substance was an acid or mixture of acids belonging to the fatty or acetic series; and he thinks he obtained certain evidence of the presence of propionic and probably also of acetic and butyric acids. Mr. Lawson Tait, of Birmingham (England), on the other hand, believes he has proved the main ingredient to be lactic acid, while Professor Will,