370 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



California are restricted to the western slope of the Nevada 

 chain, and the beeches of Chile are entirely excluded from the 

 east side of the snow-covered Cordilleras. This family also 

 manifests the usual anomalies to the general rule that the 

 zone of vegetation becomes more elevated near the equator, 

 caused by peculiarities in the form of the mountains and the 

 influence of clouds a high plateau, with stronger insolation, 

 producing a considerable elevation of the zone and the snow- 

 line, as in Bolivia and Thibet, while abrupt, isolated peaks 

 have a reverse effect. Thus Europe exhibits the influence 

 of plateaus upon the cupuliferae in two points namely, in the 

 central part of the Alps, in the weaker development and the 

 lowering of the zone of the beeches, while the pine and larch, 

 to which a mountainous climate is very favorable, form a 

 broad zone in Wallis and Granbunden, 500 to 1000 feet 

 higher than in the Bavarian Alps. Again, the chestnut 

 zone, which reaches 5000 feet on the Sierra Nevadas, which 

 rest on the plateau of Granada, does not rise above 3200 feet 

 in the same latitude in Portugal. This is owing, it is true, 

 in part to peculiar climatic conditions, which produce an un- 

 usual depression of the zones in Portugal, and which also 

 manifest themselves in rendering the zone of vegetation 

 much lower in Sumatra than in Java, on account of the dif- 

 ference in insolation, caused by the more frequent and heavier 

 clouds in Sumatra, where the axis of the mountains is per- 

 pendicular to the course of the moist, prevailing winds, while 

 in Java it is parallel to it. In this respect Portugal resem- 

 bles Sumatra, and nowhere are the effects of similar climatic 

 conditions more evident than in the southern portions of 

 Chile and in Terra del Fuego. 19 C, December 27, 1873, 489. 



EFFECT OF CARBONIC ACID AND OF OXYGEN ON THE GROWTH 



OF PLANTS. 



The effect of carbonic acid upon the germination of seeds 

 and upon the development of chlorophyl in young plants 

 has been made the subject of investigation by Boehm. Seeds 

 of sunflower, garden-cress, flax, poppy, oat, barley, rye, knot- 

 grass, and maize were allowed to germinate and grow in 

 flasks containing mixtures of atmospheric air and carbonic 

 acid, the amount of the latter varying from 2 to 50 per cent, 

 in the different flasks. The latter was exposed to diffused 



