ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 
87 
Capillarity and Ascent of Sap.*— From experiments on living and 
dead branches, the late Herr J. Boehm adduces fresh arguments in favour 
of his view that capillarity is the main agent in bringing about the ascent 
of sap and the absorption of water, and that the cells of the epiderm and 
mesophyll play the part of elastic vesicles in replacing the loss of water 
by suction from the vascular bundles. 
Internal Bleeding of Plants.f — By this term Herr B. Jonsson 
understands the excretion of water from the cells into the intercellular 
cavities of plants. He has observed the phenomenon especially in the 
Balsamineae and Cucurbitacese, but also in other plants. It takes place 
chiefly in the leaf-stalk and stem, small drops making their appearance 
first of all on the walls of the parenchymatous cells which bound the 
intercellular cavities ; and is the result of an increase in the moisture of 
the air accompanied by a fall of temperature. 
(4) Chemical Chang-es (including- Respiration and Fermentation). 
Intramolecular Respiration.}: — Herr A. Amm has made a series of 
observations on this subject, chiefly on seedlings of the lupin and wheat, 
and on the leaves and petals of the marigold and rose. The carbon 
dioxide produced was carried off in a stream of hydrogen, precipitated 
in baryta water, and the baryta determined as oxalate. The experiments 
show that intramolecular respiration is a normal, not a pathological, 
process in plants. Representing the intensity of the intramolecular 
respiration by I, and that of the normal by N, the value of the fraction 
i increases with the development of the plant ; is nearly constant with 
different organs of the same species j but differs greatly in different 
organs of the same plant. The minimum of temperature lies, with 
intramolecular as with ordinary respiration, below zero C. ; the optimum 
temperature, with seedlings, is about 40° 0., agreeing nearly with that 
for normal respiration ; the maximum temperature for intramolecular 
respiration varies with the presence or absence of oxygen. 
7. General. 
Origin of Endogens.§ — Rev. G. Henslow argues in favour of the 
origin of Endogens from an early type of Exogens, the more immediate 
cause of their origin being an aquatic habit of life assumed by certain 
primitive exogenous plants. This view is supported by arguments drawn 
from various points of structure in exogens and endogens, especially 
from coincidences in this respect between endogens generally and 
aquatic and subaquatic exogens, and such of this latter class as may 
reasonably be supposed to have had an aquatic ancestry. 
Parasites on Algae. — Mr. G. Murray || gives an account of some of 
the animal and vegetable parasites known to attack various algae, 
including the following : — The galls on Vaucheria and the malformations 
* Ber. Deutsch. Bot. Gesell., xi. (1893) pp. 203-12. 
f Bot. Notiser, 1892, pp. 225-53. See Bot. Centralbl., lv. (1893) p. 245. 
X Jahrb. f. Wiss. Bot. (Pringsheim), xxv. (1893) pp. 1-38 (2 pis.). 
§ Journ. Linn. Soc. (Bot.), xxix. (1893) pp. 485-528. 
|| Natural Science, ii. (1893) pp. 120-3. 
