
1801. ] 
tioned by Lacepede, which differs from 
the common fpecies, in being almoft en- 
tirely of a deep black. 
C. Beavvois read a memoir concern- 
ing the fox and the rabbit of America. A 
comparifon of the lean head of the Euro- 
pean fox with that of the American fox 
(Canis virginianus Gmel.);as well as of the 
European rabbit with the American (Lepus. 
Americanus Gmel.) will thew plainly that 
Buffon and other naturalifts have done 
wrong in confidering thefe as only varieties 
of the refpective European {pecies,and that 
Erxleben and Gmelin have very properly 
made them diftin@. The fox, dog, bear, 
badger, and many others of the family of 
the fere, have on the top of the fkull two 
prominent lines, which take their rife 
from the pofterior angle of the orbit, and 
are extended. backwards. In the Euro- 
pean fox thefe two lines terminate and 
unite in the future of the frontal bone, 
where they form a ridge more ar lefs pro- 
minent, according to the age of the ani- 
mal. In the American fox thefe lines are 
three times as large and well defined, and, 
inftead of uniting in the frontal future, 
they diverge from each other, and extend 
to the occipital ridge before they unite. 
The under-jaw too-of thefe two fpecies is 
confiderably different. Wherever the fhape 
of each procefs.is a well defined curve in 
the European fox, it is ftraight in the 
merican, and forms with the afcending 
proceffes an angle of near TAs? 
C. DgcaNpoLLtE communicated his 
experiments relative to the influence of 
light upon certain vegetables. 
The firft object of the author was to 
afcertain the influence of light upon the 
fleep of leaves and flowers. As the regu- 
lar vicifiitudes of day and night appeared 
to be the chief caufe of the great difficulty 
of fuch an inquiry, the author was of 
opinion that this might be obviated by ex- 
pofing the vegetables to an artificial light, 
either conftant or variouflly combined. 
For this purpofe he placed fix lamps in a 
dark cellar, and difpofed them fo that the 
plants which they illuminated fhould re- 
main in a temperature not exceeding 66° 
or 68° Fahr. and protected from the 
fmoke. Thefe fix lamps were equal to 
sacandles. The refults of thefe experi- 
ments are curious. Muftard and crefs 
feeds fown and raifed by this artificial 
light became fenfibly green, but their 
ftalks were fomewhat longer than in the 
open air. Leaves of different plants put 
under water in lamp-light gave no oxygen 
gas during twenty-four hours, end atter- 
wards they decayed and gave a deleterious 
air. . This refult might be expected, fince 
it is well knownthat plants give no oxygen 
in the fhade, and the light of fix lamps 
Proceedings of Public Societiese | 689 
cannot equal that of funfhine. The night- 
blowing Marvel of Peru (mirabilis jalapa,) 
expofed to the artificial light for three 
days, continued te open in the evening and 
fhut in the morning as ufual; the fame 
happened even in total darknefs; but on 
being expofed to the lamps during the 
day, they at firft became fomewhat irre- 
gular in the times of expanding and 
clofing, and on the fecond day they opened 
in the morning and fhut in the evening. 
The convolvulus purpurcus, which in com- 
mon opens at ten in the evening, on ex- 
pofure to lamp-light, opened at ten as 
ufual on. the firft day, but at five on the 
fucceeding day. The mefembryanthemum 
nodiflorum, expofed to the lamp-light dur- 
ing the night, and to darknefs in the day- 
time, came to open in the morning and 
clofe'in the evening. Several fenfitive 
plants, expofed for three days to continual 
lamp-light, opened and clofed each day 
two hours fooner than on the preceding 
day; whence it appears, that a contimu- 
ance of this light has haftened their move- 
ments inftead of retarding them, Ex- 
pofed to light during the night, and to 
darknefs in the day-time, their progrels 
became irregular for two days, and then 
they came regularly to open in the even- 
ing and fhut in the morning. Total dark- 
nefs did not derange their natural move- 
ments, but a heat of 80° to 100° Fahr. re- 
tarded them. A heat of 116° rendered 
them fickly, and for two days deprived 
them of their fenfibility to the touch. 
A member prefented a report concern= 
ing the Panorama, a fpecies of exhibition 
invented at London by Mr. Barker, of 
Edinburgh, and introduced into France 
by Mr. Fulton, an American, aflified by 
his countryman James, together with the 
French artifts Fontaine, Prevot, and 
Bourgecis. A view of Toulon is now 
exhibiting, which is in many refpects fu- 
perior to that of Paris, on which the firit 
trial was made. 
C. Burret, a member of feveral of the 
focieties, and a profeffor in the Lyceum of 
the Republic, has compofed a fy{tem of 
Lexicology, the merits of which have been 
examined by a commiffion from the Intti- 
tute, confifting of Cit. Danou, Tracy, 
Champagne, and Laplace. ‘Their report, 
which is unanimous, is the following :— 
That this fyftem of Cit. Butet is one of 
the beft-fitted works for the advancement 
of ideology, the beft plan hitherto known 
for the bafis of an univerfal philofophical 
dictionary, and, from its application to 
every language, is one of the fureft me- 
thods for arriving at the fundamental 
principle ef univerfal language: that the 
application of this fyftem to the fcholaftic 
inftruction of languages promifes to be 
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