Se as aaa 
a % "3 
Botany. — ae 133 : 
and now in the possession of Dr. Warren.* Cevchieshenk 
one vertebral bone might be wanting, ( Ossemens iisetineh ant me 
that the number would be the same as in the elephant.’ The dentition 
of the animal has been satisfactorily made out by Mr. Owen, who finds 
seven teeth belonging to the series of the lower jaw, counting from the 
youngest. 
It may seem unnecessary to state that the genus Tetracaulodon of 
Godmant, was clearly shown by Mr. Owen,t in 1842, to sbe only the 
immature state of both sexes of the Mastodon giganteus of Cuvier, 
and that in the male, one, atleast, and usually the right, of the two 
lower tusks was retained, but that in the female both were lost as she 
approached maturity. 
IV. Borany. 
2 Vegetable Physiology.—M. Dutrochet in connection with M. Bec- 
querel has shown that whena Chara is subjected to the action of an 
electric current, the peculiar circulation of this plant ceases for a 
while, and is recontinued after a certain period, if the current is un- 
changed ; it is discontinued in the same manner with each change in 
the intensity of the current, whether the intensity is increased or di- 
minished, 
Warittions of the temperature produce nearly the same effect, and 
it is also apparent on transferring the plant from fresh to salt water, and 
the reverse. 
Electro- ro-magnetism causes no effect, - The circulation is not at all in- 
fluenced by an electro-magnet capable of supporting near 2000 kilo- 
grammes, whether at the establishment or breaking of the current, the 
reversing of the poles, or any other mode of operation. 
M. Dutiocher concludes from these facts that the circulation in the 
Chara depends on a peculiar vital force, and not at all on electricity or 
magnetism, as the first of these, acts like all other exciting forces, and 
the second: not at all. 
2. Distribution of the Vestiges of Palms in the Geological forma- 
tions.—Prof. Unger, in the work here cited, states, Ist, that no ves- 
" tiges of palms have been detected in the earliest rocks which contain the 
Organic remains of maritime and terrestrial plants. 2d. That palms 
some small part in the vegetation at the period of the coal forma- 
tion; i in which Ferns, Lycopodiacee, Lepidodendree, Calamitez, Cyca- 
dace, and Conifers appear to have formed the principal growth. He 
names the following forms, viz. :— 
ee sa 
* See. also the Am n. Quarterly Journal lo Aglare and Lectern vol. ii, p. 203. 
*anagetiogs ef the Am. Phil. Soc., New Series, iii 
+ Proceedings of the 
