414 NOTICES OF BOOKS. 
species is found in miocene strata in Germany. Such hasty references 
are, in our opinion, particularly dangerous, and likely to lead to a great 
deal of mischief. 
Some curious experiments on the floating power of seeds, and on 
their vitality after long immersion in water, are also deserving of men- 
tion. Of 870 seeds selected from the most different natural groups, 
immersed in water for three weeks, 684 had sunk to the bottom, while 
186, or more than one-fifth, continued to float. Out of the whole num- 
ber, only 54, or very little more than six per cent., vegetated ; of these, 
28 had sunk to the bottom, and 26 were of the number which had 
floated. These numbers correspond to a proportion of four per cent. 
of the seeds which sank, and fourteen per cent. of those which floated. 
Torrey, Dr. Joun: Plante Frénontiane ; or, descriptions of plast 
collected by Col. J. C. Frémont, i» California. 4to, Washington 
City. (Smithsonian Contibutions to Knowledge.) 
Here are ten figures, and as many admirable descriptions, of Califor- 
nian plants, a portion of the collections of “Colonel; Frémont, whose 
important services to science are known to all who bave read the re- 
ports of his hazardous journeys. He has not only made valuable ad- 
ditions to the geographical knowledge of our remote possessions, but 
has greatly increased our acquaintance with the Geology and Natural 
History of the regions which he explored. His first Expedition was 
made in the year 1842, and terminated on the Rocky Mountains. He 
examined the celebrated South Pass, and ascended the highest moun- 
tain of the Wind River Chain, now called Frémont’s Peak. The party 
moved so rapidly (travelling from the frontier of Missouri to the moun- 
tains, and returning in the short space of four months), that much time 
could not be allowed for botany. Nevertheless a collection of three 
hundred and fifty species of plants was made, of which I gave an ac- 
count in a botanical appendix to his first Report. The second expedi- 
tion of Colonel Frémont, that of 1843 and 1844, embraced not only 
much of the ground which he had previously explored, but extensive re- 
gions of Oregon and California. In this journey he amassed large col- 
lections in places never before visited by a Botanist; but, unfortunately, 
a great portion of them were lost. In the gorges of the Sierra Nevada, 
