118 POPULAR FIELD BOTANY. 
and is much more common than the other. The plant in 
dryig turns black or bluish. 
CRYPTOGAMIA. EQUISETACEA. 
FouiacE&. EQUuISETACES. 
EQUISETUM. (Horss-tatt.) 
Generic Character. Stems stiff, jointed; branches, if any, 
mostly whorled. Flower, or parts of fructification, at the end 
of the stalk, in spikes or catkins. 
This singular genus of plants may easily be overlooked 
by those not interested im the study; but a botanist knows 
that by examination beauties may be found in the most 
insignificant looking weed, and that every plant has its use 
m the creation. The Hguisetum is very curious indeed. 
The spike contaming the parts of fructification appears 
before the leaf of the plant, and is oblong, with many 
stalked scales arranged on acommon stem. ‘These scales 
are angular, bearing at the back from four to seven oblong 
membranous cells parallel to each other, finally bursting into 
two equal valves. Seeds globular, very minute, having four 
spiral filaments attached to their base, which terminate each 
in a flat appendage or anther, producing pollen. Three 
