COMMON BRAKES. 
97 
the more modern writers have given it a high character for the 
same purposes, but it is now falling into disuse among medical 
practitioners : the country people, however, in Haller’s time, still 
continued to employ it for its ancient uses, and gave it as a 
powder to destroy worms; they also regarded a bed of the green 
fronds as a sovereign cure for the rickets in children : probably 
these uses are still in vogue. Its astringency is so great that 
it is used in many places abroad in dressing and preparing kid 
and chamois leather.^ 
The only British species of Cicada, the C. liccmatodes of Lin- 
neus, is said to feed, in the larva state, on the rhizoma of this 
fern : in the companion work to the ‘ History of British Ferns,’ 
I have represented this insect, together with its empty pupa- 
case, the latter still adhering to the stem of Pteris aquilina, in 
the position in which it has been found in the New Forest, in 
Hampshire, the only British locality yet discovered for the in- 
sect.f The beautiful caterpillar of a British moth [Mameslra 
Pisi) is found in great abundance on the brakes in autumn. 
The roots are brown, fibrous, and tomentous. The rhizoma 
is brown, velvety, and most extensively and rapidly creeping ; it 
generally runs in a nearly horizontal direction, but sometimes 
dips deeply and almost perpendicularly. When the London and 
Croydon railway was in progress, I found, in the New Cross 
cutting, great abundance of these underground stems in a de- 
cayed state, some of them extending to a perpendicular dejDth 
of fifteen feet. Whenever this fern has stood unmolested for a 
long series of years, the soil becomes filled with matted masses 
of these stems. The young fronds make their first appearance 
in May ; they are extremely tender, and the first shoots are 
almost invariably destroyed by the late frosts of spring ; I have 
seen them cut down to the surface of the ground as late as the 
20th of May. The young fronds come up bent or doubled, the 
leafy portion being pressed against the stem : the cut at page 
93 shows a number of young fronds in various stages of deve- 
Nearly the whole of these observations are in Haller’s Historia, aed 
Lightfoofs Flora Scotica. 
f See Familiar Introduction to the History of Insects, p. 272. 
H 
