28 
THE NATURALIST AND COLLECTOR 
ful, feathery fronds making the name 
particularly appropriate. Another of 
the common names isahay scented, or 
sweet scented, fern, given in allusion 
to the fact that the foliage, when 
bruised, gives off a strong, sweetish 
odor, akin to the smell of new-mown 
hay. The fragrance is frequently 
noticed as one walks through the ferny 
dells. This should be the true “sweet 
fern.” 
The rootstalk of the mountain fern 
is slender and creeps extensively, send¬ 
ing up its handsome fronds at short 
intervals all summer. These are lanceo¬ 
late or spear-shaped in outline, and 
are apparently endlessly divided. In 
reality, each frond consists of about 
twenty-five pairs of pinnae, which grad¬ 
ually decrease in size as they approach 
the apex. Each pinnae is divided into 
nearly fifteen pairs of pinnules, and 
the latter are again divided into as 
many lobes, which are toothed at the 
apex. 
The under side of the frond is mi¬ 
nutely hairy and glandular, the latter 
organs doubtless producing the pecul¬ 
iar odor of the crushed frond. There 
is no noticeable difference between the 
fertile and sterile fronds of this species, 
indeed, the sori 
are so small 
that one has 
to look rather 
closely to see 
them at all, 
and a magni¬ 
fier of some 
kind is neces¬ 
sary to show 
them to per¬ 
fection. Then 
it is seen that 
a reflexed toothlet of the ultimate seg¬ 
ments, usually on the upper side of 
each lobe, is holding fast a tiny green 
cup, in which the spore-cases are piled. 
The illustration shows two sori, much 
enlarged. The sori in nature are 
scarcely larger than the spore-cases 
as drawn. 
The genus to which the Dicksonia 
belongs was named in honor of James 
Dickson, an English botanist. There is 
but one species in North America, and 
this is found only in suitable situations, 
from Canada to Tennessee, and from 
New England to Minnesota. There 
are upwards of fifty species of this 
genus scattered throughout the world, 
principally in warmer countries. The 
majority of them are arborescent, or 
tree ferns. One of the tree-ferns most 
commonly seen in cultivation belongs 
to this family, and is called Dicksonia 
antartica.—Popular Science News. 
S PEL2E0L0GY is the name‘given 
by M. E. A. Martel to the 
study of caves, and a speleo¬ 
logical society has been organized in 
Paris for promoting this study. M. 
Martel has explored several hundred 
caves, finding them to be natural de¬ 
positories or museums capable of 
throwing light on many subjects. In 
their quiet recesses layer after layer 
of deposits have formed, sealing up the 
story-telling relics left by occasional 
visitors, by inundation and by per¬ 
colation. 
/T COMBUSTIBLE clay has been 
<J X found in the suburbs of Baku, 
and has been used by the 
working people as fuel for some months* 
It is burned in the form of powder, 
and gives a bluish flame of great in¬ 
tensity and without the least smoke. 
Almost every variety of corundum 
has been discovered in North Carolina. 
The opal has been found in Mexico. 
