On the Food of Green Plants. 
407 
_ wise inthe manner indicated by von Baeyer in 1870,8 viz., 
_bycondensation of formic aldehyde. Heretofore, following 
Sachs’ path-breaking researches, it has been believed that 
Starch was not only the first visible product of this process, 
| but that almost or quite all the material manufactured by the 
chlorophy1] body passed at one time or another into the form 
starch. The recent work of Brown and Morris, 1° however, 
_ Pfoves conclusively that this is not the case. ‘It is far more 
Probable,” they say,1! ‘that starch is only elaborated within 
the cell when the supply of nutriment is in excess of the cell 
requirements, and that most of the assimilated products never 
_ Pass through the stage of starch at all.” Their experiments 
_ Point to the somewhat unexpected conclusion that, at any 
_Mtein the leaves of the Tropaeolum, cane sugar is the first 
‘gar to be synthesised.” | This accumulates in the cell-sap, 
: and when its concentration ‘‘exceeds a certain amount 
1; + starch commences to be elaborated by the chloro- 
Blasts.” They add: «Our analyses point to the cane sugar be- 
- ig translocated as dextrose and levulose, and the starch as 
_ ‘Maltose, the latter 
ton of th 
f e 
" the investigation, as well as the instability of the sub- 
“i themselves, may not be known for a long time. ; 
Sur present purpose th l tion of importance 1s 
at pos e only ques 
hae the C, H,and O are, either in the form of H,CO,, 
| ‘ “T partial reduction, or in their nascent condition after 
» aS Is urged b i i If they are so com- 
bine, g y various writers. is 
thay H,Co, must be looked upon as a food, and the 
inant tctMed assimilation in accordance with long usage 
al Physiology. 
: Baye : 
’ Panzent ®) A. Von: Ueber die Wasserentziehung und ihre Bedeutung fiir das 
| Ss. “ben und die Gahrong. Ber. d. deutch. chem. Gesells. 111 (1870). 
——— ; oe 
tent nee oe des Lichtes auf die Bildung des Amylums in 
un 
5 F Tel die . 
~aern. Bot. Zeit. xx (1862). 365-373.—Also, Ueber aie 
iy bev iederbildung des per in den Chlorophyllkérnern bei 
ou ttown & means £ Bot. Zeit. xxi (1864). 289 
IS: 
604-677 
i i of fal leaves. Jour. 
“Lge o:, Exit (189, The chemistry and physiology of foliage leaves. 
“Cit. p, 673 3). 
