CHEMISTRY. 267 



other similar plants not thus treated. The experiments 

 were made with beets, maize, geranium, cabbage, etc., and 

 the results are regarded as confirming the views of Pasteur, 

 that the alcoholic fermentation produced by ordinary yeast 

 is simply an exaggeration of the normal action of all organ- 

 ic cells in the absence of oxygen. 



Wilson has presented to the British Association a paper 

 on the amount of sugar contained in the nectar of various 

 flowers. A single flower of fuchsia contains 7.59 milligrams, 

 of which 1.69 is fruit-sugar and 5.9 cane-sugar. A flower 

 of everlasting pea has 9.93 milligrams, 8.33 being fruit and 

 1.60 cane; a raceme of vetch 3.16 milligrams, 3.15 being 

 fruit-sugar, a single flower giving 0.158 milligram of fruit- 



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sugar. Ahead of red clover gave 7.93 milligrams, 5.95 be- 

 ing fruit and 1.98 cane, each floret giving 0.132 milligram, 

 0.099 being fruit-sugar; a flower of monk's-hood 6.41 mil- 

 ligrams, 4.63 being fruit-sugar. Approximately, then, 100 

 heads of clover give 0.8 gram of sugar, or 125 give a gram, 

 and 125,000 a kilogram. As each head contains about 60 

 florets, it is evident that to obtain a kilogram of sugar 

 7,500,000 florets are required. Now as honey contains about 

 75 per cent, of sugar, 5,600,000 flowers would yield a kilo- 

 gram of honey, or say two and a half millions a pound. 

 Since this nectar is only of use to the flower by attracting 

 insects to it, and in this way fertilizing the plant, as is evi- 

 dent from the fact that it is secreted at the time only when 

 the visits of insects would be beneficial i.e., when the an- 

 thers are shedding their pollen it is interesting to notice 

 the connection now pointed out between the amount of nec- 

 tar a flower secretes and the results of insect visits in chang- 

 ing the size, shape, color, etc., of the flower. 



Bohm has shown by experiment that the common opinion 

 that the starch in chlorophyll grains is in all cases the prod- 

 uct of an intrinsic synthesis from carbon dioxide and water 

 is entirely erroneous. Two positive and important conclu- 

 sions follow from his researches: 1st, that the formation of 

 starch in chlorophyll grains is in many cases the result of a 

 metamorphosis of bodies not intrinsic to the cells in which 

 this conversion takes place, but elaborated elsewhere by the 

 plant; and, 2d, that this process of conversion is entirely in- 

 dependent of the action of light, white or colored. 



