Carbohydrate Production in the Higher Plants 9 
that, in all cases, it came from organs subserving vegetative repro¬ 
duction. We should be glad to learn the characters of the starch- 
grains formed in the leaves of some of these plants for comparison. 
If all plastids arise from a common origin by division we should 
expect definite relations, on the present hypothesis, between the 
starch products of chloroplast and of leucoplast. As Reichert says, 
an enormous amount remains to be done, but the whole situation is 
full of suggestion and interest. There is however, as yet, no indica¬ 
tion that the different starches are merely stereo-isomers. The 
researches of Max Samec show what a complex colloid one has in 
natural starch. 
In conclusion, we may recall how differently the matter stands 
with the pigments of the chloroplasts from species to species. It is 
true that Etard in 1906 asserted that there were an enormously 
large number of different chlorophylls in different plants, but all 
this has disappeared before Willstatter’s demonstration of the extra¬ 
ordinary uniformity of the chlorophyll pigments throughout the 
higher plants. Influenced by this identity of pigment, we imagine 
identity in the simple first product of photo-reduction of carbonic 
acid in all cases. From this initiation the up-grade carbohydrate- 
flux proceeds; the first stage of arrest we may attribute to the 
properties of sugar molecules themselves, while the final products 
of condensation are determined by the minute chemical configura¬ 
tion of the protoplasmic agents in contact with which this condensa¬ 
tion proceeds. 
REFERENCES 
J. U. Nef. Various papers. Annalen der Chemie, Bdn. 357 , 376 and 403 . 
H. A. Spoehr. The Carbohydrate Economy of the Cacti, 1919. Carnegie 
Institution Publications, No. 287. 
D. T. MacDougal, H. M. Richards and H. A. Spoehr. Basis of Succulence 
in Plants. Botanical Gazette, 67 , 405. 1919. 
A. Meyer, fiber die Assimilationsproducte der Laubblatter angiospermer 
Pflanzen. Bot. Zeit. p. 415. 1885. 
H. Winkler. U. uber die Starkebildung in den verschiedenartigen Chromato- 
phoren. Jahv. f. wiss. Bot. 32 , 525. 1898. 
H. Lundegardh. Einige Bedingungen der Bildung und Auflosung der Starke. 
Jahr.f. wiss. Bot. 53 , 421. 1914. 
E. T. Reichert. The Differentiation and Specificity of Starches in relation 
to genera, species, etc. 2 pts. 1913 Carnegie Institution Publications, 
No. 173. 
- A biochemic basis for the study of problems of Taxonomy, Heredity, 
Evolution, etc. with special reference to the Starches and Tissues of 
parent-stocks and hybrid stocks, and the Starches and Haemoglobins of 
varieties, species and genera. 2 pts. 1919. Carnegie Institution Publica¬ 
tions, No. 270. 
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