GENERA AND SPECIES. 89 
PLATE XXXI. 
ASPIDIUM NOVEBORACENSE. Swartz. 
NEW YORK SHIELD FERN. 
This fern is even more delicate than the A. thelypteris. 
The length of the frond from the root-stock averages about 
fifteen inches. It is pinnate, lanceolate in outline, but 
tapering both ways from a point a little below the middle. 
The pinnz are lanceolate, tapering to a point; the lobes 
of the pinnz less blunt than those of the Marsh Shield 
Fern. The color of the fronds is a pale green, and is the 
same on both sides. The indusium is very minute, and, 
except in young plants is not easily seen. It is not very 
common in Kentucky, but grows luxuriantly about Living- 
ston, Rockcastle County. 
It is one of the most difficult ferns which I have at- 
tempted to draw, on account of its similarity to the Marsh 
Shield Fern, just described. The outline of the two ferns, 
especially that of the pinnz and lobes, is exactly alike in 
both. In the illustration I have tried to give the whole 
plant, showing how the pinne taper toward the base. The 
greatest difference, however, between the two ferns lies in 
the character and arrangement of the fruit-dots, and in the 
texture of the tissue of the fronds. ‘The New York Shield 
Fern is very delicate and tender; indeed almost transpar- 
ent, with the fruit-dots near the margin of the pinnule, in 
separate round patches; the Marsh Shield Fern is rather 
coarse looking, with a great profusion of sori situated in 
close, round patches, forming, when ripe, a continuous 
line. The margin of the pinnule is slightly reflexed, not 
forming, however, an indusium, as in Pteris and Pella, but 
is simply recurved. 
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