82 BOTANICAL GAZETTE [JANUAR 
influence of carbon dioxid on form and structure. Plants were grown i 
pared with normal plants; no gemmae were formed, neither the character 
istic algoid icon ais rise Air spaces and chloroplasts were much les 
abundant, but the colorless parenchyma developed normally. The resulis 
are almost exactly those of weakened light. In seed plants Teodoresco fins 
elongation. In older plants carbon dioxid favors the elongation of stems, 
the enlargement of leaf surfaces, and the rich development of bast, w 
palisades, and air spaces.— H. C, CoWLEs. 
SEVERAL PAPERS have appeared which add considerably to our knowledge 
of the Ear dpc peat Gromer vd nih aaah and carbohydrate synt 
mon, Griffon. The first paper deals chielly 
with ie relations between color and the synthesis of carbohydrates. Griffon 
shows that, although a general ratio exists between the amount and color 
the chlorophyll and the amount of CO, which is broken up, in many | 
the chlorophyll present is no measure of the chlorophyll function; for exam 
ple, in alpine plants the synthesis is greater and in halophytes it is less that 
the amount of chorophyll would lead one to expect. This result confirm 
the previous work of Bonnier, and is contrary to the view of Pfeffer. , 
some green half-parasites and symbiotic saprophytes the gas © 
associated with respiration are actually greater than those associal 
carbohydrate synthesis. The significance of these results is not cle 
the author holds that differences in the cell structure of the chloré 
explain some cases. Perhaps the most rational theory, however, is that 
are several varieties of chlorophyll, some possessing active synthetic P 
and others not; this vi ew agrees with recent spectroscopic studies by 
who claims to have found a large number of varieties of chiorep? 
sometimes two or three in one plant species. cy 
Another interesting set of results has to do with the influesiee 
other than green on the synthetic processes, Stahl, Pick, and others ha’ a 
that the red anthocyan colors favor synthesis, whereas Jumelle and 
have held that they retard it. Griffon thinks that they have no 
whatever. Although red leaves commonly do less chlorophyll work 
en leaves in related species, this is due to the generally smaller 
of Ghicsrophgil in red leaves. Red leaves rich in chlorophyll are as 
green leaves of _ a or # stiniiag bcanes Nor does the autho 
y prej , even though red lea 
Ann. Sci. Nat. Bot. VILL. 10: I-323. 1899. 
