ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
359 
BOTANY. 
A. GENERAL, including the Anatomy and Physiology 
of the Phanerogamia. 
a. Anatomy. 
CD Cell-structure and Protoplasm. 
Aggregation of Protoplasm. — Dr. P. Klemm * urges further ob- 
jections against the application of the term “active albumin” to the 
precipitations caused in living cells by the action of coffeine or other 
alkaloids, or of ammonia or ammonium salts, on the protoplasm of the 
living cell. He considers it probable, either that the aggregated substance 
and the albumen of living protoplasm are different bodies, or that the 
silver reaction is not an infallible diagnostic for the hypothetical active 
albumen. 
As the result of observations on very thin sections, Dr. Klemm 
adduces further arguments against Bokorny’s view that the aggregation- 
precipitates produced in this way in the hypodermal cells of Crassulaceae 
take place in the parietal utricle of protoplasm ; he states that they are 
located exclusively in the cell-sap. 
Dr. T. Bokorny replies, f especially on the second of these two points, 
basing his arguments on observations made on the living cell rather than 
on microscopic sections. 
Physodes.J—Herr E. Crato records the result of further observations 
on these structures, which he regards as an essential constituent of living 
cells. The protoplasm has always a reticulate structure, the size of the 
meshes varying greatly ; sometimes they are comparatively large, as in 
Cladophora, sometimes visible only under the highest powers of the 
Microscope. In the lamellae which separate these meshes are imbedded 
the nucleus, the chromatophores, and the physodes ; and the spaces are 
filled up by a hyaline fluid which he calls the “ chamber-fluid,” com- 
prising the cell-sap and the enchylema. The physodes, to which most of 
the microsomes belong, serve especially for the transport of assimilable 
substances ; they contain the most readily oxidizable substances of the 
cell, and travel periodically between the nucleus and the periphery of 
the cell. This movement is independent of the streaming of the proto- 
plasm. 
The author has investigated these structures, especially in the brown 
algee (Fucaceae and Phaeophyceae), where they are of almost constant 
occurrence. They occur also abundantly in the hairs and in the green 
cells of many flowering plants. Their size varies greatly, even within 
the same cell. The physodes almost invariably contain substances allied 
to phenol, especially phloroglucin. Their micro-chemical reactions are 
given in great detail. The author has come to the conclusion that 
neither the physodes nor the lamellae of the reticulate protoplasmic 
framework contain albumen ; the staining reactions from which its 
presence has been concluded are due to substances allied to phenol. 
Bot.jCentralbl., lvii. (1891) pp. 193-9, 225-9 (2 pis.). Cf. this Journal, 1893, 
p. 345. f Tom. cit., pp. 2:10-2. 
X Bot. Ztg., li. (1893) l te A.bthsil., pp. 157-96. Cf. this Journal, 1893,3p. 58. 
