ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
363 
produce a diastatic enzyme on carbohydrate soil. The latter is not so 
easily separated from the microbes which produce it ; but when that has 
been accomplished, its action on starch can still be demonstrated. This 
diastatic enzyme has no effect on gelatin. The bacteria are capable of 
evincing an adaptiveness to the soil in which they grow. The microbes 
are capable of digesting other similar bodies such as dextrin and 
muscle, but were not found to have any influence on fat. 
y. General. 
Phenomena of Etiolation.* — Dr. E. Godlewsld points out that it is 
incorrect to sjieak of etiolated organs as sickly, at least in their early 
stages. The chief characters of etiolated parts of plants, viz. smallness 
of the leaves and lengthening of the internodes, the smaller degree of 
firmness, and the larger amount of water, and, in the case of Mono- 
cotyledons, the greater breadth and smaller length of the leaves, are all 
of advantage to the underground parts, in diminishing the consumption 
of food-material. It is only when the duration of these characters is 
unduly prolonged in the parts exposed to the air, that the plant becomes 
sickly and finally dies. By observations made on Phaseolus multiflorus^ 
the author demonstrated that the average proportion of water is con- 
siderably greater in the etiolated portions beneath the surface of the soil 
than in the parts exposed to the air. 
Influence of the Sea on the Structure of Leaves.j — M. P. Lesage 
finds, from differences in structure in leaves of individuals of the same 
species grown near to or remote from the sea, that the effects of the 
saline air and soil are to increase the thickness of the leaf, and especially 
the development of the palisade-parenchyme ; to diminish the inter- 
cellular spaces ; and to decrease the amount of chlorophyll in the cells. 
B. CRYPTOGAMIA. 
Cryptogamia Vascularia. 
Stem of Selaginellacege.| — M. Yladescu describes the structure of 
the various tissues which compose the stem of Selaginellacege, especially 
those which proceed from the middle of one of the three cells which 
result from the third division of the original initial cell of the stem. 
From the further segmentation of the middle and internal of these 
segments proceeds a conducting tissue, consisting of the vascular tissue, 
the liber- tissue, and the conducting parenchyme ; this last comprising 
the fascicular parenchyme (Strangparenchym), pericycle, endoderm, 
trabecular cortex, and internal cortex. The boundary, therefore, between 
the central cylinder and the cortex cannot, as Yan Tieghem proposes, be 
placed bet ween the pericycle and the endoderm ; rather, all the tissues 
outside the liber must be referred, with Treub and Russow, to the 
cortex. All the tissues above described in the stem occur again in the 
root, and with a perfect continuity between the corresponding tissues in 
the two organs. 
* Biol. Centralbl., ix. (1889) pp. 481-9, 617. 
t Comptes Rendus, cix. (1889) pp. 204-6. 
X Jouru. de Bot. (Morot), iii. (1889) pp. 261-6. 
