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SUMMARY OF CURRENT RESEARCHES RELATING TO 
BOTANY. 
A. GENERAL, including the Anatomy and Physiology 
of the Phanerogamia. 
a. Anatomy. 
Cl) Cell-structure and Protoplasm. 
Structure of Protoplasm.* — By the use of very high powers, Herr 
E. Crato claims to have established that the protoplasm of a cell always 
consists of a connected honeycomb-like or reticulate framework ; though 
in certain instances (cilia of swarm-spores, stinging-liairs of TJrtica) 
there appear also to be homogeneous threads of protoplasm. All the 
essential constituents of the cell — the nucleus, chromatophores, and 
physodes — are to be found in the threads or lamellae of protoplasm. 
In the brown algae ( Giraudia sffihacelarioides') the protoplasm obvi- 
ously consists of a moderately regular network of pentagons or hexagons. 
In the formation of new cells, the cell is first of all divided into two 
halves, between the two new nuclei, by a septum formed of homogeneous 
protoplasm. The physodes move towards this septum and supply the 
materials for the formation of a layer of cellulose within the septum of 
protoplasm. This is followed by an increase in the vacuoles. 
In the higher plants (stinging hairs of TJrtica pilulifera, growing 
point of Elodea canadensis ) the network of protoplasm is composed of 
finer meshes, and cannot be so clearly made out. The cilia of swarm- 
spores appear to consist of threads of homogeneous protoplasm ; but 
they also contain typical physodes. 
Nature of the Physiological Elements of Protoplasm.! — Herr W. 
Detmer concludes, from the phenomena presented by protoplasm in the 
living cell, that each micella consists of a number of living molecules of 
albumen ; and that the atoms of which these molecules are composed 
are in a state of unstable equilibrium. The structure of living proto- 
plasm may undergo more or less rapid changes : — thus it may pass from a 
reticulate or honeycomb structure into one which is apparently or 
actually homogeneous, and then back again to its original condition by 
a process of rejuvenescence. 
It would further appear that there must be specific differences in the 
physiological properties of the cytoplasm and of the elements of the 
nucleus in different species, founded on their chemical nature and con- 
stitution ; and that these differences find an expression in the relation- 
ship between the amount of carbon dioxide given off in their normal 
and in their intramolecular respiration. Designating the former by N, 
the latter by I, then the proportion — would seem to be nearly uniform 
for different organs of the same species, but to vary greatly in different 
species. Thus, for the ray-florets of Calendula officinalis it is 0 • 205, 
for the leaves of the same plant 0*221 ; for petals of the rose 0*527, for 
leaves of the rose 0 * 648. 
* Ber. Deutsch. Bot. Gesell., x. (1892) pp. 451-8 (1 pi. and 1 fig.), 
f Tom. cit., pp. 433-41. 
