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have been named and described. Of these, Cormophyilum horridum 
(Polypodium horridum of Linneus, and Hemitelia horrida of Robert — 
Brown), Cormophyllum arboreum (Polypodium arboreum of Linneus, 
and Cyathea arborea of Smith), and Cormophyllum capense (Polypo- 
dium capense of Linneus, and Alsophila capensis of John Smith), may 
serve as examples. The three genera Hemitelia, Cyathea and Also- 
phila have never been distinguished by any natural character; but 
the genus Cormophyllum may possibly be divided hereafter; the ve- 
nation seems to offer diagnostics. 
Family DRYOPTERIDE. 
The caudex ‘vertical, but subglobose or tufted, never forming a 
trunk, but always exhibiting a crown of undeveloped fronds. This 
family contains all our most familiar ferns. Dryopteris Filix-mas, 
Polystichum aculeatum, Athyrium Filix-femina, Pseudathyrium al- 
pestre, Asplenium Adiantum-nigrum, and Notolepeum Ceterach are 
familiar examples. 
Family RuIzocoRME. 
In which the caudex creeps horizontally in the earth, extending 
itself in various directions; the fronds being solitary and distant; the 
growing point of the root-like caudex is, however, invariably com- 
posed of undeveloped fronds. Examples, Hemestheum Thelypteris, 
(the Polypodium Thelypteris of Linneus), Gymnocarpium Dryopteris 
(the Polypodium Dryopteris of Linneus). 
Family PTeripEz. 
Crown less scaly ; stipes less scaly ; fructification marginal. Hx- 
amples, Blechnum spicant, Pteris longifolia, Cheilanthes odora, Adi- 
antum Capillus-Veneris. 
That these families do not comprise all the annulate ferns [ am well 
aware; but they comprise all the more conspicuous groups; and none 
of those which are omitted offer, as far as I am aware, any serious 
obstacle to the physiological arrangement. The order in which they 
are here described is not intended to show anything of the relation- 
ships which exist among them. These cannot readily be expressed 
on paper. Perhaps the following formula may give some idea of my 
views on this subject; and it must be observed that some of the families 
