152 
PROCEEDINGS OF SOCIETIES. 
their distribution, often crossing one another in their course ;■* generally fruitful. 
Examples—Pol. Angulare (var. strictum—K.) ; Phyl. scolopendrium, var. margi¬ 
natum (Wol.), Truncatum, subvariety—frond contracted; segments either lobed or 
reduced to a mere midrib ; generally symmetrical; the apices of the pinnse and pin¬ 
nules often truncated, and then unsymmetrical; nervures as in laciniatum; generally 
barren. Examples—Am. ruta mura, subvar. truncata (K.). These groups, especially 
the variety, present a most extraordinary variety of forms, agreeing all in the one cha¬ 
racter of absence of some normalpart ofthe fern. They appear to be divided into seve¬ 
ral groups, according to the element affected, but unfortunately we do not always find 
the same element affected two successive years. The general type ofthe class is always 
adhered to, one year the deficiency occurring in one set of elements, and the next, 
perhaps, in another; however, when the substance of the frond is present, we find 
it cut and lobed, though sometimes it is entirely wanting. The following, or, 
in fact, any of the elemental parts ofthe fern, may be wanting. The green colouring 
matter, the frond variegated and lobed on the edges, as Ph. Scol., var. subvari- 
gatum (Wol.) ; Aspl. A.N., var. variegatum (W.). The substance of frond ; either 
in part the frond lobed in various ways; or entirely the pinnse and pinnules or 
frond itself reduced to mere lines, as Pol. Ang., var strictum (Kin.). The epider¬ 
mis deficient in some way, its edges scalloped and tucked, often pitted and thick¬ 
ened ; the apices ending in a spur of fibres, as in the forms marginatum, &c., of 
Phyl. Scol. and Lomaria spicant, var. marginatum (W.). In fact, every conceiv¬ 
able variety of deficiency occurs, and renders the study of numerous examples of 
this class necessary for the comprehension of the whole. This variety is much less 
permanent under cultivation than either of the others, but still sufficiently so to be 
distinguished from the subvariety. Some of its forms are most beautifully symme¬ 
trical, in so much that they have been mistaken for species, as the Polystichum, 
found at Kew, with angularly linear leaflets, which bears the name of Angustatum, 
and has the habit of producing bulbillagf in the axils of its leaves ; a habit also of a 
beautiful example of this group exhibited by me before your Society, in 1852, in a 
plant of Pol. angulare. The Kew plant, or, at least, those plants shown me as 
such, I believe to belong to Pol. aculeatum, an opinion I know at variance with the 
generally received one. The preceding remarks, also, in a great measure, apply 
to the subvariety, in which we find the same irregularities of form—the same 
occasional symmetrical arrangement of parts—the same tendency to a viviparous 
reproduction. $ The subvariety in this group is, however, much seldomer fertile 
than the variety ; it is also very often uniform, but never permanently so. The 
laciniate subgroup varies more under cultivation than any other, but always 
keeps sufficiently near to the type to be recognised easily from any other, except 
the subvariety Truncatum, between which and it some confusion exists at present, 
principally arising from the groups not having (owing to its ugliness) been as 
much studied as the Ramose or cristate type, but, doubtless, after a little more exami¬ 
nation, it will be found as well defined as that group. I have prepared a list of all 
the forms that appear to belong the groups mentioned to-night, but can look on 
them as, to a certain extent, imperfect, as, doubtless, forms belonging to other groups 
are mixed up with them, owing to a want of specimens and information about the 
plants. Indeed, I think, the class themselves are, to a certain extent, only pro¬ 
visional, containing within them, probably, the nucleus of other classes. My object 
has been to collect together all the abnormal forms, and, as far as possible, group 
them; how far or how naturally this has been done it must remain for others to 
judge. A few words about a point of nomenclature. When a variety and sub- 
variety are found in conjunction it is proposed to call the form by the name of the 
variety, merely adding after it, “ in combination with subvar., &c. when two 
varieties or subvarieties are conjoined, either to name it after that best marked, or 
make a similar addition to that above, or to call it after both, as we speak at pre¬ 
sent of u red and white” roses, &c. To the names used some may, and, doubtless, 
* As in Ph. Scolopendrium polyschides (Ray) which possesses a netted venation. 
t This habit of producing bulbils is found in two other species of British ferns—viz., Am. Ruta 
muraria, where the fronds are generally multifid and fruitful, and in Phyl. Scolopendrium (Galway, 
Dr Allchin), where the fronds are normal and fruitful. 
t Seen in Polyst. Angulare, vide also Newm. Brit. Ferns., Ed. 3rd., Polystich Ang. varieties. 
