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THE POPULAR SCIENCE MONTHLY, 



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 num- 

 ber. On March 25th, four had germinated, 

 viz., Lepidium ruderale, L. sativum, Sinapis 

 alba and Brassica napus, all Cruciferas. On 

 May 15th, besides the foregoing, the follow- 

 ing seeds had germinated : Arabis alpina, 

 yEthionema saxatile, Brassica nigra, Petro- 

 selinum sativum, Cannabis sativa, Ervum 

 lens, Pisum sativum, Avena sativa, Secale 

 cereale, Hordeum vulgare, Triticum vulgare. 

 Hence it appears that the seed of Cru- 

 ci ferae and of Grarninese freely germinate at 

 the temperature of zero C. Of the seeds 

 named above, about an equal number ger- 

 minated 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 fur Wissenschaft- 

 liche Zoologie. There are some salt-marshes 

 near Odessa, which in 1871 contained num- 

 bers of Artemia salina, a minute crusta- 

 cean, 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 Baume 

 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 sa- 

 lina was modified from generation to gen- 

 eration, so that, by the end of 1874, several 

 individuals had no caudal lobes (see figure 

 of A. salina in No. 20 of the Monthly, 

 December, 1873), and they presented all 

 the specific characters of Artemia Mulhau- 

 aeni. The changes observed from -year to 

 year are minutely described. They appeared 

 especially in the caudal part, and were ac- 

 companied by diminution of size. These 

 observations were confirmed by experi- 

 ments made on Artemia kept in water of 

 various degrees of softness. In the inverse 

 experiment from a greater to a less soft- 

 ness, A. Mulhauseni returned to'the form 

 of A. salina. As the saltness increased or 



decreased, there was an increase of dimi- 

 nution of the surfaces of the bronchia?. The 

 writer of the article further gives reasons 

 for thinking that the genus Artemia is 

 only a degraded form of Bronchipus, de- 

 graded through the influence of the me- 

 dium. 



Clothing the Yonng. " Hygiene ot 

 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 cir- 

 culation 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 cere- 

 bral affections have been, apparently with 

 good reason, referred to this cause alone. 



An Antomatie Light-Registering Machine. 



Mr. Crookes has made an ingenious appli- 

 cation of his radiometer to meteorological 

 purposes. In our present meteorological rec- 

 ords we note variations in heat, rainfall, at- 

 mospheric pressure, etc., but light, the most 

 important influence, has been neglected hith- 

 erto, for the want of a machine for automati- 

 cally registering its variations. Mr. Crookes 

 has arranged the arms of his radiometer so 

 that they carry round a small magnet sus- 

 pended beneath them. The amount of light 

 falling on the pith-balls at the extremities of 

 the radiometer arms determines the rate 



