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BOTANY. 
CoLorine anb Dryine or Naruran Frowers.— Mr. Muir gives 
the following abstract of this paper, by E. Puscher (Dingl. Polyt. 
J. cev, 891-2.) The flowers ‘are placed in a glass funnel, which 
is inverted over a plate containing a few drops of sal ammo- 
niac solution. After a few minutes, most blue violet or bright 
carmine-colored flowers change to a Schweinfurt green; dark car- 
mine flowers become black, white change to sulphur-yellow. The 
flowers plunged into fresh water retain their new colors for 2-6 
hours, and then lose them. By a somewhat similar treatment with 
hydrochloric acid, many flowers, especially asters, may be colored a 
beautiful red, which is lasting after the flowers are carefully dried. 
THE INFLUENCE or COLORED LIGHT on ASSIMILATION BY PLANTS. 
— E. Lommel (Pogg. Ann. cxlv, 442.) (Abstr. by E. Kinch.) 
enumerates many of the conclusions arrived at by different experi- 
menters on this subject, and considers it a well-ascertained fact 
that the greatest amount of decomposition is produced by those 
rays which are absorbed by chlorophyll, and have at the same 
time a high mechanical intensity. Solid chlorophyll shows the 
ee 38 
tween the interstices of the chlorophyll cells usually forms a con- 
tinuous spectrum over the absorption bands, and so dims or wholly 
obliterates the paler ones, whilst the band i suffers only a slight 
diminution in intensity. The theory of the author is supported 
by the direct experiments of N. J. C. Müller (Bot. Untersuchungen, 
Heidelb. 187 1) and by the following experiment. 
Two similar bean-plants were placed in frames, the sides and 
top of the first of which were composed of a combination of blue 
cobalt glass and red copper glass, which allowed only the red rays 
between 4 and B to pass through; in the second, a combination 
of red and violet glass was used, which transmitted only the mid- 
dle red rays. Both conbinations were so dark that the plants could 
scarcely he seen from the outside; their power of transmitting 
heat rays was almost identical. At the end of a week, the first 
plant was sickly and had not increased in size, whilst the young 
leaves of the second plant had doubled in size, and it gt to 
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