100 HANDY BOOK OF 
the fields become white with snow, but still the Black 
Spleenwort rejoices the passer-by by its ample and luxuriant 
fronds. 
We have spoken of the roots, and the rhizoma, the scales, 
and rachis. It now remains to notice, that the frond is 
triangular in form that the apex is acute and attenuated 
that it is pinnate, with triangular pinnre, acutely pointed, 
pinnate, and alternate ; whilst the pinnulee themselves are 
alternate and triangular, the lower ones pinnate, or pin- 
natifid, with notched lobes. 
It is needful, likewise, to observe that the side-veins in 
the lobes, or pinnula 1 , are irregularly alternate, and mostly 
forked after diverging from the mid-vein. One or both 
branches of this divided vein bear an elongate linear mass 
of theca), situated near the mid- vein, and at first completely 
covered by a long, narrow, white, scale-like indusiuin, 
Avhich opens towards the mid- vein. When the thecse swell, 
and approach maturity, this small scale is gently raised and 
pushed from its site ; it is next turned aside, and finally 
disappears, when the under surface of the frond presents a 
. continuous mass of rich brown seeds. 
We may lastly remark, in the words of a brother botanist, 
" that the superior length of the lower pinnae, and the 
oblique angle at which these, and indeed all the pinnae, are 
attached to the rachis, with the more central position in the 
pinnulae occupied by the thecsc, are characters by which the 
Black Spleenwort may be readily distinguished." 
