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Rh their small, toothless mouth, but it is nevertheless important in its prehensile capacity. The condition of the specimen is of course a deformity, but appears to be the result of a want of development of the jaws, and not of accidental violence. Such fishes are often caught in the Ouachita, and occasionally even they have been reported without a vestige of an oral orifice. If the latter condition really occurs, the fish can only supply itself with food and with water for respiration through the branchial fissures, by the alternating outward and inward movements of the opercula.

Hatching Frogs under Colored Glass.—In an experiment made by M. Thury, the eggs of Rana temporaria, a species of frog, were placed under identical favorable conditions, with the exception that some of the eggs received light through colorless glass, and others through green glass. The former developed rapidly, and by the end of May had a length of over one and a half inch, and well-developed hind-legs in most of them; the others were slowly developed, blackish in color, hardly had a length of three-quarters of an inch by the end of May, and were without a trace of hind-legs. By the 10th of June the former had their fore-legs, and some were changed to frogs; the others, still black, had no trace of legs, and breathed almost exclusively by means of their gills. By the 15th of July the one lot had become frogs; the others still had no legs, and by the 2d of August they were all dead, without a trace of legs having appeared. Some of the young of this lot, transferred to the vessel in which were contained the developed frogs, finished their metamorphosis.

Equine Idiocy.—A plant known in California as "rattle-weed" is said to produce in animals which eat of it symptoms much resembling those of amentia and frenzy. A correspondent of a San Francisco newspaper, writing from Monterey County, describes as follows the effect produced by this plant on a herd of fifty horses on a ranche in the southern part of that county: "They became," he says, "crazy, forsook the farm, and wandered off one by one over the plain, paying no attention to their mates or any thing else. They were too muddled in their brains to seek for water, and most of them died of thirst. Although they were wild, and had never been handled, any person could walk up to them on the plain and hit them with his hand, when they would jump, perhaps, straight up in the air, perhaps some other way, and act as though they were trying to leap a fence at every step. They seemed to retain their sight, yet would not turn aside for any thing. The poor demented beasts would walk over a precipice without the slightest fear or hesitation."



Cincinnati Industrial Exposition of the present year includes a Department of Natural History and Antiquities, and prizes are offered for the best collections in geology, and mineralogy, conchology, zoology, botany, numismatology, and archaeology. The managers promise that the greatest care will be taken of all specimens sent in for exhibition. The prizes consist of silver and bronze medals.

form of snow-spectacles has been devised for the use of the British arctic expedition. These spectacles have neither glass nor iron in their composition; they are made of ebonite, and tied on the head by a velvet cord. They somewhat resemble two half walnut-shells fastened over the eye, and the wearer sees through a simple slit in front of the pupil. To give the wearer a side view, the sides of the eye-box are perforated with minute holes. These spectacles are said to be of great service in reading by lamp or gas light.

Royal Agricultural Society of England has the most numerous membership of any similar association in the world. It has on its roll 5,846 names. Its "Transactions" are published in half-yearly volumes.

Phylloxera vastatrix has made its appearance in England. At a meeting of the London Entomological Society, Mr. McLachlan exhibited a portion of a vine-leaf on which were the galls of Phylloxera. The leaf had been plucked in a greenhouse near London.

pneumatic-electric apparatus for lighting and extinguishing street-lamps is now in practical operation in a large part of the business portion of Providence, Rhode Island. The principle of this apparatus consists in a combination of compressed and rarefied air to open and close gas-cocks, and an electro-galvanic current, affording a spark to light the gas. It enables a single 