486 
Dubourg’s Museum, with additions, 
is now open, at No. 68, Lower Grosve- 
nor-street, with large cork models of 
temples, amphitheatres, mausoleums, 
&c. from the most admired remains of 
antiquity in Rome, Italy, and the South 
of France. Cork gives an admirable 
Proceedings of Learned Socteties. 
[Dec. 3, 
idea of ruins; the sponginess which it 
naturally exhibits, when cut in the pro- 
per manner, gives a something that re- 
semble the_ravages of the teeth of time, 
more than any art can produce. Mr, 
Dubourg’s specimens are eminently cu- 
rious, 
- PROCEEDINGS OF LEARNED SOCIETIES. 
NATIONAL INSTITUTE OF FRANCE. 
REPORT of the TRANSACTIONS of the Pliy- 
SICAL CLASS of the NATIONAL INSTI- 
TUTE, for the last HALF YEAR of 1806. 
By M. cUvIER, SECRETARY fe the socI- 
ETY. 
(Continued from page 377.) 
DE LA BILLARDIERE has 
h e completed twenty-two numbers 
of his Flora of New Holland. 
Five new genera, we are informed, are 
therein described, one of which, in par- 
ticular, termed by this Botanist athero- 
sperma, and which he considers as be- 
longing to the family of the ranunculi, is 
a tree hkely to become very useful in 
France, as the kernel of its fruit pos- 
sesses the taste and odour of the nutmeg, 
and as it appears very capable of sup- 
porting the temperature of that climate. 
One of our most celebrated corre- 
spondents, M. Humboldt, continues to 
publish, in conjunction with his fellow 
-traveller, M. Bonpland, the plants they 
have discovered in South America. Two 
pumbers of this interesting work have 
already appeared. We are likewise in- 
debted to these indefatigable. travellers 
for so many new species belonging to the 
family of the melastoma alone, that they 
might form a volume by themselves. 
These learned naturalists, continues 
M. Cuvier, have been equally industrious, 
and successful in their researches into 
the natural history of animals. 
The Condor, a bird so famous in the 
Cordilleras, had never been accurately 
described before their time, and its size 
had always been greatly exaggerated. 
According to their description it 
scarcely exceeds one metre in height, 
or more than three or four metres in 
thickness. Its colour is commonly a 
blackish brown; and the lower part of the 
neck is furnished with a ring of white 
feathers. The male is discriminated’ by 
a fleshy crest on the crown of the head, 
and by a white spot uvon the wing, marks 
which are not found in the female. 
The observations of these two travellers 
upon the electrical eel of Surinam, 
gymnotus electricus, are in M. Cuvier’s 
opinion, extremely curious. This fish, 
which is very.common in several of the 
marshes of Guiana, gives such violent 
shocks as to stun horses, make them fall 
down, and expose them to be drowned. 
It is in this way, that we obtain possession 
of the gymnotus, because when the 
animal is exhausted by a quick repetition 
of these shocks, it may “be seized with 
impunity. M.de Humboldt, in placing 
his feet on one of these electrical eels, 
after being drawn out of the water, 
experienced so severe a shock, that the 
iinpression left by it contimued the whole 
‘day, and disqualified him from judging 
of its true nature; but when only slight 
shocks are communicated, they produce 
a particular tremulous motion, a species 
of subsultus tendinum, which occurs not 
in ordinary electrical shocks. The effects 
produced by those of the gymnotus more 
particularly resemble the pain which is 
occasioned on galvanizing a wound, The 
shocks depend on the will of the animal, 
which gives them without making any 
apparent motion, and directs them ac- 
cording to its pleasure. In proportion, 
as itis better fed, and the water more 
frequently renewed, in which it is kept, 
the shocks are more violent; but they 
cease to be communicated, on depriving 
the animal of its brain and heart. They 
may be propagated through the same 
media_as those of electricity; it is not, 
however, sufficienc to come into contact 
with the water, in which the animal is kept 
in order to receive a shock; but neither — 
is it necessary to this effect to form a 
circle, or to touch the animal in twa 
points, 
M. Tenon, has given an important 
continuation of his Memoirs upon the 
Dentition of the Horse. : 
After briefly recapitulating the re- 
sults he had presented to the Institute 
‘in former years, he dwells, at considera~ 
ble length, on the three last molares, _ 
or grinders, in each jaw. ay 
The lower teeth have two roots; those 
