142 
PROCEEDINGS OF SOCIETIES. 
Dr. Kinahan then read a paper 
ON THE ABNORMAL FORMS OF FERNS. 
When, on a previous occasion, I called the attention of this Society to the sub¬ 
ject of abnormal forms among the ferns, I stated my suspicion that some general 
law or laws would he found governing them in their entirety, as a class, and 
thereby enabling us to group them. I then laid before you a sketch of the groups 
into which, in conformity with these supposed laws, forms might be divided. This 
scheme, crude at that time, has, thanks to the contributions of specimens by 
friends, and additional opportunities of examination afforded to myself, since been 
confirmed in most of its details, so that the following may be set down as esta¬ 
blished:—1st. That the aberrant forms of ferns obey certain fixed laws of form. 
2nd. In accordance with these laws, that they may be divided into two great 
groups, bearing certain relations to each other, similar, and yet perfectly distinct. 
3rd. That these great groups may be subdivided into parallel subgroups, each sub¬ 
group in the one representing a subgroup in the other, totally irrespective of 
generic or specific distinctions. To examine and illustrate these laws will be my 
task to-night. First, a few words to remove a misapprehension which I find 
many labour under w r ith regard to former remarks made on this subject. It is not 
the object of this scheme to establish new species—far from it; with species, as 
such, it has nothing to do, solely dealing with the morphology of the plants under 
consideration, totally irrespective of species or genus. 
These two great classes, as was before stated, possess strong analogies both to 
one another and within themselves, yet are perfectly distinct, never running into or 
producing one another, though we may find a group of the one class in accidental 
combination with one of the other. These two groups, for which I proposed the 
names, variety, and subvariety, will be found to possess the following distinctive 
characters:—Variety is universally a permanent aberrant form, affecting all the 
fronds of the plant— i.e. : uniform; under all circumstances of cultivation preserving 
its distinctness, and occurring generally in isolated plants ; if fruitful, often pro¬ 
ducing its own form. Subvariety, an aberrant form, seldom permanent under 
cultivation, affecting only a few fronds, often occurring in numerous plants of a 
district, and from its spores producing the normal form—this is sometimes perma¬ 
nent under cultivation, but never uniformly so. The essential difference between 
these two classes then, in brief, is—variety, a permanent, uniform monstrosity, and 
subvariety, a monstrosity not necessarily permanent nor uniform— ex. gr ., in 
Lomaria spicant, var. ramosum , every frond each year dichotomously rounded at the 
apex, while Lorn, spicant, subvar. multifidum, though much resembling it in gene¬ 
ral character, has some years all the fronds dichotomous, other years, perhaps, a 
single frond dichotomous, and other years none at all—in fact, in this the great 
difference consists between the two divisions; in the first, the monstrosity depend¬ 
ing on some radical change in its nature, once imprinted on the plant is nearly 
indelibly so, extending often even to the produce of the spores (as we see in some 
monstrous forms of Athyrium), while in the subvariety, the monstrosity depending 
on some mere local or climatal influence, is liable to change as these are modified 
or removed. It is not meant to be asserted that varieties will not sometimes 
change under cultivation into another seemingly different variety, or that the spores 
will not produce plants of the normal type, but that this much may be taken as 
proved—that variety never changes into subvariety, or subvariety into variety; 
therefore, the statement put forward, to the effect that variety ramosum is but a 
form of subvariety multifidum , is based on error. Another grand distinction 
between the two, in a state of nature, is, that seldom or never do we find the variety 
in more than one or two plants at most, while the subvariety is often found more 
or less pervading the plants of a district— ex. gr., there is a little stream glen at 
the base of the greater Sugarloaf, where L. spicant, subvariety multifidum , may 
always be found, some years every plant bearing fronds more or less divided, in 
other years you will only get single plants so affected, while the variety ramosum 
was found affecting only a single plant. The same might be said of the variety 
ramosum , and subvariety multifidum of Ath. incisum ; and all varieties found in 
collections will be found to have had their origin from a few isolated plants found 
