500 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
The first effect of a wound is the development of schizogenous 
glands which are subsequently converted into lysigenous spaces. These 
facts were verified both for styrax liquidus from Liquidambar oriental is, 
and for sweet gum from Liquidambar styraciflua. The experimental 
proof was furnished by L. Planchon, who found that balsam did not 
exist in normal plants, and that it occurred only after wounding the tree. 
The author supports this by noting the result of making semi- 
circular cuts in a Liquidambar styraciflua 6 metres high. Where the 
branches were not wounded there was no trace of balsam ; but where 
the damage had affected the cambium, rows of balsam glands could be 
detected with a lens. It seems therefore indisputable that storax is a 
pathological product. 
Cellulose Enzymes.* — Prof. F. C. Newcombe has made a series of 
experiments on those enzymes which have the capacity of dissolving 
reserve-cellulose or starch (cytases or diastases). The following are 
the more important results. 
The enzyme extracted from Aspergillus Oryzse attacks reserve- 
cellulose with greater intensity than it attacks starch. The enzyme 
from the cotyledons of seedlings of Lupinus albus is very strongly 
cytohydrolytic, but very feebly amylohydrolytic. The same is the 
case with the enzyme from the cotyledons of seedlings, and from the 
endosperm of Phoenix dactylifera. These enzymes act so feebly on 
starch, and so energetically on reserve-cellulose, that they may be 
regarded as cytases as distinguished from diastases. The very dilute 
enzyme of the malt of barley attacks reserve-cellulose. With all the 
enzymes examined (those of Aspergillus Oryzse , Phoenix dactylifera , 
Fagopyrum esculentum , Pisum sativum , and Lupinus albus), the walls of 
the cells attacked become at first hyaline and gradually more and more 
transparent, finally disappearing altogether in solution. 
(3) Structure of Tissues. 
Elastic Swelling of Tissues, j* — Herr C. Steinbrinck discusses, from 
a physical point of view, the phenomena connected with the curvature 
of the tissues in the bursting of anthers, and of the sporanges of ferns, 
Equisetum , &c. 
Physics of Cohesion-Mechanism. :J — Herr C. Steinbrinck treats this 
subject from a mathematical point of view. With regard to the pappus 
of the Cynarese, he agrees with Zimmermann, and with a paper (in 
Russian) by Taliew, that the movement of the hairs is not merely a 
passive one, but that they have in themselves a “ shrinking-mechanism,” 
which can be demonstrated, by their optical phenomena in polarised 
light, to be due to the structure of their cell-membranes. In the 
majority of the Composite this mechanism is, however, rudimentary; 
the greater part of the movement is due to the “ cohesion-mechanism ” 
of the cushion which bears the hairs. This cushion is well described 
by Taliew. In the contraction of tissues, the force which drives the 
water into the contracted cells, and smooths out the folds in their walls 
* Ann. of Bot., xiii. (1899) pp. 49-81. 
t Ber. Deutsch. Bot. Gesell., xvii. (1899) pp. 99-112. 
t Tom. cit., pp. 170-8. 
