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122 1872, at a temperature of -8° C., and they were taken out on May 15th. In 1873, they were placed in the ice-houses in February, the temperature being -5° C., examined on March 25th, and removed on May 15th. The kinds of seed sown were twenty-five in number. On March 25th, four had germinated, viz., Lepidium ruderale, L. sativum, Sinapis alba and Brassica napus, all Cruciferæ. On May 15th, besides the foregoing, the following seeds had germinated: Arabis alpina, Æthionema saxatile, Brassica nigra, Petroselinum sativum, Cannabis sativa, Ervum lens, Pisum sativum, Avena sativa, Secale cereale, Hordeum vulgare, Triticum vulgare.

Hence it appears that the seed of Cruciferæ and of Gramineæ freely germinate at the temperature of zero C. Of the seeds named above, about an equal number germinated in ice and in earth. The radicles had penetrated the blocks of ice. Those seeds which had not germinated lay rotten on the surface of the ice or of the soil.

Transformation of Species.—An instance of transformation of species is recorded as follows in the Zeitschrift für Wissenschaftliche Zoologie. There are some salt-marshes near Odessa, which in 1871 contained numbers of Artemia salina, a minute crustacean, also known as the brine-worm. At that time, owing to the rupture of a dike, the quantity of salt in the pond was very small, the water marking 8° in the Baumé areometer. The dikes were repaired, and concentration then proceeded rapidly until, in September, 1875, the water marked 25°. As the salt was increased the Artemia salina was modified from generation to generation, so that, by the end of 1874, several individuals had no caudal lobes (see figure of A. salina in No. 20 of the December, 1873), and they presented all the specific characters of Artemia Mulhauseni. The changes observed from-year to year are minutely described. They appeared especially in the caudal part, and were accompanied by diminution of size. These observations were confirmed by experiments made on Artemia kept in water of various degrees of softness. In the inverse experiment from a greater to a less softness, A. Mulhauseni returned to the form of A. salina. As the saltness increased or decreased, there was an increase of diminution of the surfaces of the bronchiæ. The writer of the article further gives reasons for thinking that the genus Artemia is only a degraded form of Bronchipus, degraded through the influence of the medium.

Clothing the Young.—"Hygiene of Dress" is the subject of a series of articles in the Sanitary Record. The author's remarks concerning the proper clothing of infants and children are judicious. "Warmth," he says, "is the first requisite for infants, who are very susceptible to cold. The clothing of the infant should be both light and warm. Its purpose is to protect the infant from chills, or rather to prevent too great a loss of heat. It should be ample enough to prevent any pressure on the blood-vessels, which would impede the circulation and hinder the free development of the members. It should be especially easy over the chest, in order to insure the free play of the lungs and heart, and should be equally ample around the stomach and the intestines, in order not to interfere with digestion. The sleeves should be wide, in order that the garment may be easily put on, and to favor the circulation of the blood in the arteries and veins of the arms and legs. The robe should be long enough to preserve the infant from cold, but not so long as to be a burden. The head should not be covered. A cap often tends to favor congestions; sometimes, too, it compresses the head, and certain cerebral affections have been, apparently with good reason, referred to this cause alone.

An Automatic Light-Registering Machine.—Mr. Crookes has made an ingenious application of his radiometer to meteorological purposes. In our present meteorological records we note variations in heat, rainfall, atmospheric pressure, etc., but light, the most important influence, has been neglected hitherto, for the want of a machine for automatically registering its variations. Mr. Crookes has arranged the arms of his radiometer so that they carry round a small magnet suspended beneath them. The amount of light falling on the pith-balls at the extremities of the radiometer arms determines the rate