Foop PLANTS. 67 
upon their boots and any scraps of leather they could find; and the 
Lapps would be unable to keep their reindeer, were it not for the 
abundance of cladonia rangiferina, or reindeer moss, on which these 
animals chiefly sustain themselves. Iceland moss (cetraria islandica) 
is a nutritious food for man, and much valued asa mild mucila- 
ginous tonic in catarrh, consumption, and other diseases. Two 
species of Lecanora form important articles of food in Persia, 
Armenia, and the adjacent countries. They appear in some seasons 
in such enormous quantities that in certain districts they cover 
the ground to the depth of several inches, and the natives believe 
they fall from heaven. In 1829, during the war between Russia 
and Persia, there was a great famine in Oroomiah, on the south- 
west of the Caspian; and one day, during a violent wind, the 
whole face of the country was covered with one of these lichens, 
which fell in showers. In 1846, in the Russian province of Wilna, 
the ground was covered several inches deep by a fall of one of them. 
Other similar falls have been recorded. It has been attempted to 
identify these lichens with the manna on which the Israelites were 
fed during their wanderings in the Arabian desert. They pro- 
bably grow with a very slight attachment, or none, to the ground, 
and, driven by the wind, fall like rain. One of the species is also 
eaten by the Kirghiz Tartars under the name of earth bread, and 
another both by men and animalsin Algeria. But of all cryptogam- 
ous plants the most available as food are the fungi. The flesh of 
fungi resembles in many respects that of animals, and in 
some cases it is similarly flavoured. During the civil war 
in the United States, when food, and especially meat, was scarce 
and dear, an American mycologist says their value was much appre- 
ciated by those able to discriminate them There are at least from 
40 to 50 species in this country which are harmless, but many of 
the others are virulent poisons; so that nobody should meddle 
with them unless he is able with certainty to distinguish the whole- 
some from the poisonous. What adds to the danger is that the 
symptoms do not appear until the venom has been absorbed into 
the system, when remedies are too late. In all cases it is well to 
infuse the mushrooms, even those commonly used, in a strong 
brine of vinegar and salt before cooking ; it is possibly owing to 
this method of preparation as much as to difference of soil and 
climate that the Russians and other foreigners are able to eat 
species that are deadly poisons with us. Agaricus campestris is 
