1823.) 
zontal. Tho intermediate shelves rise 
up, obliquely, on each side. M. Prevost 
has represented this sort of a natural 
cup, in a drawing, which is rendered 
still more intelligible by an ingenious 
colouring. The grand divisions of the 
land are distinguished, in their general 
character, and with their subdivisions, 
and so al! the facts that compose the 
geological history of the country are in- 
cluded. A description is subjuined of 
the fossils, as well as of the couches or 
strata that contain them, Among 
others, is a species of reptile, named 
ichthyosaurus, partaking of the nature 
of a lizard and a fish, and the most 
ancient, perhaps, that we are acquainted 
with. There are, also, fishes, with some 
unknown species of crocodiles and 
cerites, a species of shell-fish that abound 
in the rocks, and are found scattered in 
heaps, one among another, but sepa- 
rated by very thick strata of chalk, on 
which none of them are found. 
M. Dutrochct has made additional 
experiments on the direction which the 
different parts of plants take, from ger- 
mination to their complete develop- 
ment. He has fonnd, that when grails 
are turned, and their axis of rotation is 
inclined to the horizon, though but 
slightly, the two seminal caudexes take 
the same direction, and the radicle fol- 
lows that inclination. If the axis be 
perfectly horizontal, the two caudexes 
take a direction in a tangent to the very 
small circle described by the embryo. 
In stalks that have leaves, when sub- 
mitted to the rotation, the leaves turn 
their superior faces towards the centre of 
rotation, and the petiole, or supporting 
stalk, bends conformably to that dis- 
position. 
M. Dupetit Thouars considers the 
flower as a transmutation of the leaf, and 
of the bud that depends on it. His ex- 
periments on the juice of vegetables, 
present facts which seem no further 
connected with that substance than as it 
is an assembiage of veyetable fibres, 
such as would be no less observed in 
other assemblages that have not the 
properties of the juice. It is generally 
supposed that a tree, deprived of its 
bark, loses ifs power of vegetation. 
M. D. T. has peeled trees, for three 
years together, and they have sustained 
no injury. He thinks the elm endures 
this mutilation the best, but the oak de- 
eays under if. A young peeled elm 
produced, at first, some protuberances 
That took a greenish tint, and were soon 
Academy of Sciences. 
251 
found to be buds. These disappeared, 
in winter; but, in the spring, there ap- 
peared a number, large enough to recom- 
mence a new tree. 
M. Raffeneau Delille, professor of 
botany at Montpellier, and a corres- 
pondent of the academy, has described 
a singular plant, of the family of cor- 
bels, or gourds. On the same stalks it 
bears hermaphrodite and male flowers. 
lis frnit, nearly two feet in length, and of 
a proportionate thickness, is covered 
with a resinous and inflammatory pow- 
der, plentiful enough to be gathered by 
scraping off. The author judges it to 
be analogous to the vegetable wax of 
the myrica cerifera of North America, 
and to the same of the ceroxylum 
andicola, discovered in the Cordilleras 
by Messrs. de Humboldt and Bonpland. 
M. Jacquin, from whom M. Delille 
received the grains of this plant, has 
named it beninaga cerifera. 
M. de Humboldt is publishing the 
tenth uumber of his superb Collection 
of Mimosa, and, in conjuction with M. 
Kanth, the twenty-second number of 
the new Genera and Species of the Tor- 
rid Zone. M. Kanth bas published the 
first volume of a Treatise, wherein he 
éxamines, afresh, the Characters of the 
Genera of the Family of Mallows, also 
those of the Ciliaceous and Butnera 
kind. 
M. Richard, whose death in the course 
of this year the academy have had to re- 
gret, had left a paper on the Family of 
the Balanophorcos, which has been 
presented by his son, a young botanist, 
the worthy representative of a family, 
that, for near a century, has been ren- 
dering service. to the science of vege- 
tables, . 
M. Dupetit Thouars has presented 
the commencement of an History of the 
Plants of the Family of Orchis. This 
forms part of a Flora of the Isles of 
France and Bourbon, which M. D. T. 
has been long employed upon. 
Several physiologists attribute the 
faculty of absorbing exclusively to the 
lymphatic vessels; some others, how- 
ever, allow it also to the veins, for all 
that is not chyle. This question has 
been, of late, the subject of renewed 
discussion, M. Segelas bas communi- 
cated to the academy, and repeated, 
before its committee, some experiments, 
which not only confirm, in general, the 
absorbent faculty of the veins, but 
prove, aiso, that certain substances are 
only absorbed by those vessels, or, at 
least, 
