1922] CURRENT LITERATURE 337 
a conception favors the chemical theories of photosynthesis which assume that 
chlorophyll itself enters into the reactions, rather than those which assume 
that the synthetic reactions are performed externally to the chlorophyll by 
means of energy absorbed and transformed by the pigments. 
That the light actually displaces electrons seems to be proved by Drxon 
and BALL‘, who show that the chlorophyll acts as a sensitizer of photographic 
films at the temperature of liquid air, a temperature believed to be too low 
for chemical reactions other than electronic displacement. They suggest that 
chlorophyll a and 8 might have an important connection in the synthetic pro- 
cess, as indicated by the following equations: 
C;sH7,0;N,Mg+CO.>C,;H,.OsN,Mg+ HCHO 
(chlorophyll a) (chlorophyll 8) 
C;;H»OsN,Mg+ H,0—>C,;H,,0;N,Mg+O, 
(chlorophyll 8) (chlorophyll a) 
e fact that in vitro experiments with chlorophyll a and CO, do not yield 
formaldehyde could be explained by accepting W1LisTATTER’s assumption 
that before the CO, will react with the chlorophyll it must first be combined 
into a carbamino acid, which can then be decomposed by the reactive group 
in the chlorophyll, which group was rendered reactive by the electronic shifting 
due to light. 
Regardless of whether the discovered facts are sufficient to establish the 
relations between Siecenonie: eapateent and aynthess a. carbohydrates, 
the attempt made by 
the newer conceptions os ae i checikey is ‘praiseworthy, and will be 
followed with great interest by physiologists. Ultimately all the chemical 
processes of life must be interpreted along similar lines.—C. A. SHULL. 
The mycoplasm theory.—In two brief notes in English and an extended 
discussion in German, ErrkssoNs makes a spirited defense of his mycoplasm 
cory. Only aactleliad reference is made in these papers to the work on the 
grain rust, on which the theory was established, but the previously published 
conclusions on the downy mildew of spinach, the late blight of potato, and the 
hollyhock rust are reaffirmed, critics are replied to, not without acerbity, and 
in the case of the hollyhock rust new observations and experiments are adduced 
which, the author believes, still further support his hypothesis, of which he is 
not only the originator, but has been, to date, almost the sole protagonist. In 
4 Drxon, HENRY and Batt, NIGEL G., os se si the electronic 
sme IL. Notes Hee Heal Trinity Coll., Du blin 3 205. 
get stabs The mycoplasm theory, is it feaatas or — a Phytopath, 
II: 3 — itt 
— ° life of bes aegis Mont. within the host plant and on its 
surface. Phytopath 112450-4 
mn des aliciotel Izes (Puccinia malvacearum Mont.) in und 
auf der Neicplencs, Handl. Kungl. Svensk. Vetensk.—Akad. 625:1-190. figs. 31. 1921. 
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