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PTEEIS AQUILINA. 
mid-vein produces side-veins in opposite pairs, which are 
variously branched; these branches unite at the edge of 
the segment, and where they unite is the fructification. 
This is in a continued line, the masses of spores being 
covered with a whitish membrane, which seems to be 
an extension of the outer skin of the leafy segment. 
This Fern is variously modified by the situation in 
which it grows; its segments are sometimes quite entire- 
edged, and.this variation has been called integerrima. 
In another variation the edges of the segments are 
excessively curled or crisped. This, however, differs 
from the Pteris crispa of some botanists, which we have 
described as Allosorus crispus. 
It is useless to particularise the localities of this Fern, 
for it is found on barren heaths and in woods wherever 
the soil is a siliceous sand. It is much rarer in districts 
where chalk abounds. 
Turner, writing of this Fern in 1502, says in tho 
second part of his “ Herbal,”—“ Not onlye the opinion 
of the commen people is that the Feme hath sede, but 
also it is the opinion of a Christen Physicion, named 
Hieronymus Tragus, who doth not onlye saye that 
Ferns hath sede, but wrytith that he founde upon myd- 
somer even sede upon Brahes. I have taken oute of his 
herball his wordes concernynge that matter, and havo 
translated that into Englishe after this maner followinge. 
Although that all they that have written of herbes have 
affyrmed and holden that the Brake had nether sede 
nor frute, yet have I dyvers tymes proved the contrarye, 
whiche tliinge I will here testefye. I have foure yores 
