40 
BEAUTIFUL FERNS. 
side. They are attached to the rachis by a very short and slender 
stalk. Their usual form is dimidiate-oblong ; that is, they appear 
as if cut in two longitudinally, and the lower half removed, so 
that the lower edge is entire, and straight, or often slightly hol- 
lowed ; the base, or edge nearest the rachis, is also straight and 
entire ; it is parallel with the rachis, or even overlaps it a little ; 
the upper edge is more or less lobed or incised, but in general 
nearly parallel with the lower, and the end is rounded and slightly 
lobed. The point of attachment is, of course, at the angle between 
the lower and basal edges. The terminal pinnule of each pinna, 
and the basal one, which, indeed, very often proceeds from one 
of the recurved branches just below the origin of the pinna, are 
broadly cuneate or transversely oblong in shape, the two sides 
which meet at the point of attachment being equal ; and the few 
pinnules near the basal one are shorter and more triangular than 
the middle ones. The texture is delicately membranaceous, but 
elastic ; the color is a lively green, and both surfaces are very 
smooth. The upper surface appears to be destitute of stomata ; 
and this may be the reason why water will not adhere to the pin- 
nules, but either falls off, or stands in spheroids ready to fall. The 
veins are free: in the 'Symmetrical basal and apical pinnules the 
veinlets fork repeatedly from the very base ; but in the oblong 
middle pinnules there is a faint principal vein running close to the 
lower edge; and from this the veinlets diverge obliquely, and fork 
about three times before reaching the superior margin. The incis- 
ions of the superior margin are usually very narrow, and extend 
only to about one-third of the breadth of the pinnule ; but in some 
