ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
503 
False Dichotomy.* * * § — Herr J. Wiesner describes an example of this 
mode of branching in Xanthopliyllum vitellinum. He also gives further 
illustrations of his classification of the various modes of the branching 
of lateral shoots under three heads, viz. : — (1) epitrophic, the stronger 
growth of the lateral shoot which springs from the upper side of a 
lateral mother* shoot ; (2) JiypotropMc, the stronger growth of the lower 
lateral shoot of an inclined mother-shoot ; (3) amphitrophic , the stronger 
growth of a lateral shoot of an inclined mother-shoot. 
Anatomy of Leaves.f — M. E. Pee-Laby has made an exhaustive 
study of the anatomical structure of the leaves of grasses, natives of 
France, which he classifies under six categories. The characters of 
these six classes are described in detail, as respects the epiderm, the 
chlorophyllous parenchyme, the veins, and the supporting tissue. 
Hydathodes of Conocephalus ovatus.J — Herr G. Haberlandt states 
that if the normal hydathodes of this plant, belonging to the Urti- 
cacese, are destroyed, there appear, on the under side of the leaves, blad- 
ders, caused by the raising up of the epiderm, which performs the same 
function in taking up an excess of water. 
Stomates of Monocotyledons.§— Herr H. Miehe confirms, in all es- 
sential points, Strasburger’s account of the processes of cell-division 
which take place in the formation of the stomates in Monocotyledons 
(. Iris ). The mother-cell of the stomate arises from the division of an 
epidermal cell into a larger and a smaller cell, the two guard-cells being 
then formed by a longitudinal division of the latter. The nucleus of 
the epidermal cell moves towards one end of the cell, where the mother- 
cell of the stomate originates, and the nucleus of the larger half then 
returns to the centre. The mother-cell of the stomate is always separated 
from the end of the epidermal cell nearest to the apex of the leaf. Herr 
Miehe now describes the process in great detail, and states that, although 
the two cells are so unequal in size, the amount of protoplasm in the 
two is about the same. The movement of the nucleus cannot be 
explained, in the opinion of the author, by physical causes (gravitation). 
It depends on the fact (as can be clearly seen in Hyacinthus) that the 
nucleus of epidermal cells is connected with the parietal layer by strands 
of protoplasm ; and this also accounts for the fusiform shape of the 
nucleus. The wall of the nucleus is stated to be composed of kino- 
plasm. 
Trichomes of the Gesneracese.|| — Dr. K. Rechinger describes the 
remarkable trichomic structures which are found in many genera of 
Gesneracese, as a type of which may be taken those of Smithiantha cinna- 
barina, the chief characteristic being the partial or entire filling up of 
the terminal cell by a hyaline mass. They do not occur in all the 
genera, and the variations in their form and structure are described in 
as many as 83 different species. The cell-walls of the swollen cells 
may or may not be thickened. 
* Ann. Jard. Bot. Buitenzorg, 1898, 2 me Suppl., pp. 97-102 (1 pi.). 
f Ann. Sci. Nat. (Bot.), viii. (1898) pp. 227-346 (4 pis. and 18 figs.). 
I ‘ Ueb. experimentelle Hervorrufung eines neuen Organes bei Conocephalus 
ovatus,’ Berlin, 1899, 119 pp. and 2 figs. See Bot. Ztg., lvii. (1899) p. 211. 
§ Bot. Centralbl., lxxviii. (1899) pp. 321-30, 353-9, 385-93 (1 pi.). 
|| Oesterr. Bot. Zeitschr., xlix. (1899) pp. 89-92, 142-6, 180-3, 207-13 (1 pi.). 
