30 
BEAUTIFUL FERNS. 
A. spinulosum genuinum, indicating the fact that the basal 
pinnules are shorter than the next. Dr. Gray also examined 
the Willdenovian specimens of intermedium, and his notes 
show that he recognized in them what we now call van 
^intermedium. Willdenow’s words “ pinnulis pinnatifido-incisis ” 
also point towards van intermedium ; since of A. spinulosum 
he says; “pinnulis inciso-dentatis.” It is therefore right to 
keep for this form the time-honored name of intermedium ; 
and to consider it a variety of A. spimdosum, because neither 
in the form and details of the frond, the position of the sori, 
nor the glandulosity of the surface and indusia can any specific 
distinction be fairly discovered. 
Var. dilatatum has dark-green deltoid-ovate or broadly 
ovate ^ fronds often considerably larger than in the other 
forms : Milde gives three feet as the extreme length, but 
such fronds are rarely preserved for herbarium specimens. 
The pinnae diverge from the rachis at from sixty to eighty 
degrees. The lowest ones are frequently but not invariably 
longest, but always broadest : in one example from Mount 
Mansfield they are eight or nine inches long, and five 
inches wide at the base. They are broadly triangular, 
nearly twice pinnate, the secondary rachis wingless and the 
tertiary very narrowly winged, and the inferior basal pin- 
nules are over three inches long. The inferior basal pinnules 
are longer than the next ones in this form, but the supe- 
rior basal pinnules are shorter than the next. The pinnules 
generally are so deeply pinnatifid as to render the frond 
