B O T AN Y. 



RAPID GROWTH OF VEGETABLES IN HIGH LATITUDES. 



In a recent treatise on the vegetable productions of Norway, Dr. 

 Mueller relates some extraordinary facts respecting the influence of 

 the long duration of light, during the summer months, on the growth 

 of vegetables in the higher latitudes of Norway. At 70 N. it was 

 found that peas grew at the rate of three and a half inches in twenty- 

 four hours for many days in summer, and that some of the cereals 

 also grew as much as two and a half inches in the same time. Not 

 only is the rapidity of growth affected by the constant presence of 

 light, but those vegetable secretions which owe their existence to the 

 influence of actinic force on the leaves are also produced in far 

 greater quantity than in more southern climates ; hence the coloring 

 matter and pigment cells are found in much greater quantity, and the 

 tint of the colored parts of vegetables is consequently deeper. The 

 same remark applies to the flavoring and odoriferous matters ; so that 

 the fruits of the north of Norway, though not equal in saccharine 

 properties, are far more intense in flavor than those of the south. 



NATURE OF THE GAS PRODUCED FROM DECOMPOSITION OF CARBO- 

 NIC ACID BY LEAVES EXPOSED TO LIGHT. BY M. BOUSSINGAULT. 



Referring to the history of discovery in respect to the relations of 

 plants to the atmosphere, Boussingault remarks that Bonnet first took 

 notice of the emission of air from the surface of leaves ; Priestly recog- 

 nized this air to be oxygen ; Ingenhouse proved the presence of light 

 to be necessary ; and Senebier proved that the oxygen gas eliminated 

 by leaves under the light of the sun came from the decomposition of 

 carbonic acid gas. Saussure, nearly at the beginning of the present 

 century, ascertained the fact which has often been overlooked 

 that the volume of oxygen gas produced was not quite equal to that 

 of carbonic acid decomposed ; and also that nitrogen gas was always 

 evolved to an amount of the oxygen gas which had somehow disap- 

 peared. He supposed that this nitrogen came from the substance of 

 the plant, not considering, what is now obvious, that the substance of 

 the plant did not contain, and therefore could not have furnished, 

 anything like this quantity of nitrogen. 



In modern times, Daubeny was unable to obtain from leaves oxygen 

 gas free from azote ; and Draper states that he found the astonishing 

 amount of from twenty-two to forty-nine per cent, of the gas emitted 

 from the leaves of Pinus tceda and Poa annua to be nitrogen. The 



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