FILICINE.E. 
CLASS VIII. 
FI LI CI NE^. 
The plants included in the group of the Filicineae are distinguished from the 
Equisetacese and from the Dichotomeae by the various and complete development 
which their leaves attain. In proportion to the stem, the leaves are always of con- 
siderable size, and in their anatomical structure, as well as in their external form, 
they manifest a higher differentiation than do those of the two groups above 
mentioned. In these two groups the whole external form of the plant depends upon 
the formation and branching of the stem, and the most important physiological 
functions are performed by this organ; in the Filicineae the stem is essentially an 
organ for bearing leaves and roots ; its growth is slow, frequently its development is 
so imperfect that no internodes are formed, whereas the leaves are endowed with an 
active apical growth which continues for a considerable time and in some cases is 
unlimited. Further, the stem, in the Filicineae, has but litde tendency to branch ; in 
whole families it remains simple, and not unfrequently the formation of buds is 
provided for by the leaves in which a strong tendency to branch is manifested, and 
which present, in consequence, the most varied forms of pinnate and palmate 
segmentation and of dichotomous branching. In the Equisetace^ and Dichotomese 
it generally happens that the stem takes part in the formation of the fructification ; 
in the Equisetacese it is always and in the Dichotomeae it is usually an apical 
spike which is terminal upon the branch bearing it. In the Filicineae this is never 
the case ; the function of reproduction is discharged solely by the leaves, the stem 
taking no part whatever in it. The leaves bear very numerous sporangia (the 
number varying with the size of the leaf), whereas the peltate scales of the Equise- 
taceae bear but a few, and the fertile leaves of the Dichotomeae only one. The mode 
of development of the sporangia upon the leaves of the Filicineae. is not uniform ; 
in the Stipulatae each sporangium arises from a group of epidermal cells, in the 
Filices and Rhizocarpeae from a single epidermal cell ^ 
It appears, moreover, that the Rhizocarpeae, which were formerly separated 
from the Ferns on account of the mode in which their fructification is developed, 
present (more especially the Salviniaceae) a sufficient number of resemblances to the 
true Ferns to justify us in regarding them as a branch of the ancestral tree from 
which the Hymenophyllaceae and Polypodiaceae have sprung. 
It is not easy to give a brief account of the relationships existing between the 
groups contained within this class, for a v;hole series of Ferns, the Osmundaceae, 
Schizaeaceae, and Gleicheniaceae have been as yet but imperfectly investigated from a 
morphological stand-point. Our present knowledge (1874) of these plants is very 
superficial, it suffices merely for the diagnoses of systematists. For those who 
can obtain the necessary material and who possess the requisite morphological 
' [See Goebel, he. cif.'] 
