THE RIGID BUCKLER FERN. 
Lastrea rigida. — Presl. 
This Fern is of moderate size, growing from a foot to 
two feet in height, erect, and spreading, the fronds 
annual, springing from the crown of a comparatively 
thick scaly tufted stem, or caudex. It is one of the 
most elegantly divided of the Lastreas, the pinnules 
being all doubly and very evenly serrated, or toothed. 
The fronds are narrowly triangular, rarely somewhat 
lanceolate, bipinnate, with narrow tapering pinnae; 
comparatively small, and generally broadest at the 
base, always covered with minute glands, giving off a 
pleasant balsamic fragrance when bruised, to be smelt 
also in the sunshine from the untouched plants. The 
outline of the pinnules, bluntly oblong with shallow 
lobes (differing in this from the other native species 
of the genus), is most nearly approached by some 
forms of Filix-mas incisa , and the serratures also, as in 
that, are not at all spinulose or bearded, but short and 
merely acute (it is, however, distinguishable from that 
by its size, its outline, its glandular surface, and its 
glandular-fringed indusium). It can hardly be mis- 
taken for any other of the Lastreas , nearly all the rest 
of them having spinulose serratures. 
The stipes is densely scaly, The venation is similar 
