498 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
BOTANY. 
A. GENERAL, including tlie Anatomy and Physiology 
of the Phanerogamia. 
a . Anatomy. 
Cl) Cell-Structure and Protoplasm. 
Chemical Energy of Living Cells.* — Herr O. Loew further dis- 
cusses the energy of living protoplasm, giving the results of a large 
number of recent observations. The present volume treats of the 
causes of vital activity, the general characteristics of living substance, 
its chemico-physiological characteristics, the essential accompaniments 
of protoplasm, the character of biochemical work, the formation of 
albumen in the lower fungi and in cliloropkyllous plauts, the theory of 
the formation of albumen, a transient proteinaceous substance as a 
reserve-substance in plants, the chemical characteristics of proto-protein, 
motility and activity in protoplasm, the theory of respiration. The 
motility of protoplasm is brought about by the concurrence of aldehyd 
and amide-groups ; the oxydases cannot be regarded as the source of 
respiration. 
Periplasmie Membrane.f — M. IVT. Ts^vett contests the conclusions 
to which Chodat and Boubier have come | with regard to the ecto- 
plasmic layer or parietal utricle of living cells. In opposition to them, 
he maintains his previous view that this periplasmie layer is not merely 
a molecular layer, but is a distinctly differentiated membrane, an organ 
of the cell. Although there is a distinct adherence between this mem- 
brane and the underlying hyaloplasm, this does not imply any insensible 
transition from one to the other. 
Kinesis in the Pollen-grains of the Liliaceae.§ — M. Y. Gregoire 
differs from previous observers — Farmer, Mottier, Strasburger, and 
Sargant — with regard to the processes which take place in the formation 
of the pollen-grains of Lilium. He states that the kineses are accom- 
panied by two longitudinal divisions at right angles to one another, and 
pre-arranged, from the first kinesis, by the formation of tetrads. The 
chromosomes do not undergo any transverse division, and there is there- 
fore no reduction division in Weismann’s sense. The bodies described 
by some writers as centrosomes he believes to be nucleoles. 
Nuclear and Cell-division in Solannm tuberosum.|| — Dr. B. Nemee 
has followed out these processes in the apices of the stem and root of 
the potato, and in the tuber during the formation of the periderm re- 
sulting from injury. The differences in the development of the 
achromatic division-figure are of great interest, showing distinctly that 
even in the vegetative tissue of the same plant the development of the 
achromatic figure may differ in essential particulars, and that external 
* ‘Die chemische Energie d. lebenden Zellen,’ Miinchen, 1899, xi. and 175 pp. 
See Bot. Centralbl., lxxviii. (1899) p. 341. 
t Journ. de Bot. (Morot), xiii. (1899) pp. 79-82. 
X Cf. this Journal, 1898, p. 637. § Bot. Centralbl., lxxviii. (1899) pp. 1-3. 
|| Flora, Ixxxvi. (1899) pp. 214-27 (2 pis. and 9 figs.). 
