1907] CURRENT LITERATURE 227 
the character of the reaction, or by altering both. Cases of this kind are cited 
from his own researches and those of KLeBs, RorHert, VOcHTING, and others. 
This variation in sensitiveness has a parallel in that of other physiological char- 
acters, as, for example, the behavior of aerobes toward oxgyen, luminescence, 
pigment-formation, etc. The specific effect of acids and alkalies is likened to the 
effects of H+ and OH7— ions on various functions. Other observers, notably 
HIBATA, have shown similar chemotactic sensitiveness of spermatozoids to both 
anions and cathions. 
The author points out “‘interesting and far-reaching analogies” between the 
chemischer Sinn of bacteria and the corresponding Geschmackssinn of man, and 
suggests that further investigations may find these phenomena more complicated 
than they now appear.—C. R. B 
Camptotrophism and geotrophism.—Two new terms are added to the vocab- 
ulary of irritable phenomena, and some interesting reactions described b 
Bicuer.?5 It appears that when a shoot capable of growth is forcibly bent, it reacts 
to the tensions thereby set up by thickening the walls and reducing the cell diam- 
eter in the mechanical tissues (collenchyma, bast, wood) on the convex side, and 
conversely, forming thinner walls and larger cells on the concave side hi 
reaction is due to Kamptotrophismus, being interpreted as belonging to the same 
category as WIESNER’s heterotrophisms. In like manner when a similar shoot, 
geotropically sensitive, is fastened in the horizontal position and prevented from 
ascribes to geotrophism. It is unfortunate that the new term is so like the well- 
established geotropism, with which it will be difficult to prevent confusion, even 
in English speech. 
Simple strain, in the normal inline as Ee sabe does not effect such 
anatomical changes; but bot the phenomena 
referred to. The peeseinbasioe. time varies from 24 to 48 hours and the reaction 
time in Ricinus and Phaseolus is about 3 days. Forcible curvature and re- 
Strained geotropic response combined give a summation effect; opposed, one 
usually prevails strikingly over the other. In Ricinus the geotrophic, in Abaiiloh 
and Euphorbia the camptotrophic response dominates. A similar reaction was 
found in heliotropic stems; analogously, heliotrophism may be predicated. In 
the excentric growth of the lateral branches of trees there are special reactions 
which affect the activity of the cambium and its differentiation, but geotrophism 
is restricted to young parts. Various observers have shown that there are also 
other causes for heterotrophism.—C. R. 
Life-history of cotton.—Batts*° has studied the life-history of Gossypium 
from floral development to the early stages of the embryo. Aborted anthers are 
2s Bicuer, H., Anatomische Veranderungen bei gewaltsamer Kriimmung und 
geotropischer Induktion. Jahrb. Wiss. Bot. 43:271—360. figs. 40. 1906. 
26 Batts, W. L., The sexuality of cotton. Reprint from Yearbook of the Khe- 
divial Agric. Soc. Cairo. 1905. pp. 26. pls. 9 
