496 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
BOTANY. 
A. GENERAL, including the Anatomy and Physiology 
of the Phanerogamia. 
a. Anatomy- 
(1> Cell-structure and Protoplasm. 
Irritability of Protoplasm.* — Herr E. Strasburger gives a resume 
of all that is at present known with regard to the morphological 
structure and the physiological properties of vegetable protoplasm, and 
the part which it plays in the phenomena of irritability in the vege- 
table kingdom. It is accompanied by a copious bibliography. 
Plasmogenous Vacuoles in the Nucleole of the Endosperm.f — M. C. 
Decagny finds similar phenomena in the nucleole of the endosperm 
of Phaseolus to that which he has already recorded in the case of 
Spirogyra. The mode of observation was by hardening ovules from 
1 to 5 mm. in length in absolute alcohol or Flemming’s solution, 
colouring by picrocarminate or the violet mixture obtained with the 
aid of fuchsin or methyl-green, and then mounting in glycerin with 
the addition of the same staining reagents. By this means plasmo- 
genous vacuoles could be detected, containing in solution a substance 
which solidifies in contact with the nuclear sap and the cell-sap. When 
this substance solidifies in the form of a membrane, it exhibits the 
homogeneity, transparency, and index of refraction of the nuclear 
membrane, of the membranous layer of the protoplasm, and of the 
achromatic filaments which arise from the indirect division of the 
nucleus. It follows from this that the origin of the plasmic substances 
such as the nuclear membrane, the achromatic filaments, and those which 
present similar properties and reactions, must be sought for in the 
nucleole, and therefore in the nucleus, not in the cytoplasm. 
(2) Other Cell-contents (including 1 Secretions). 
Substances which accompany Chlorophyll in Leaves. :f — M. A. 
Etard records the elimination of the following substances in leaves. 
When the leaves of the vine are treated with carbon disulphide, 
a portion of the substances thus extracted is soluble, and a portion 
insoluble, in alcohol. The soluble portion yields a substance with the 
composition C 17 H 34 0, which he calls vitol, and a substance soluble in 
ether, a diatomic alcohol to which he gives the name vitoglycol , with 
the empirical formula C 23 H 44 0 2 , and probably the true composition 
C 23 H 42 (OH) 2 . This is accompanied by a triatomic alcohol, cenocarpol. 
A similar treatment of the leaves of lucerne yielded a monatomic alcohol 
medicagol , with the formula C 20 H 44 OH. From Bryonia dioica a hydro- 
carbon C 20 H 42 was obtained, which the author calls bryonane. The 
mixture of these, together with crystalline paraffins, probably constitute 
the substances to which the term wax of leaves has been applied. CEno- 
carpol, C 26 H 39 (0H) 3 H 2 0, was found also in the pericarp of the grape. 
* ‘ Das Protoplasm u. d. Reizbarkeit,’ Jena, 1891. See Bot. Centralbl,, 1. (1892) 
p. 48. 
t Comptes Rendus, cxiv. (1892) p. 245. Of. this Journal, 1891, p. 58. 
% Tom. cit., pp. 231-3, 364-7. 
