St. Helena species of this genus, and originally noticed in Pritchard's list of the plants of that island as Hym. capillare, has the receptacle more nearly as described, though I shoidd rather have called it clavate than " apice globoso-incrassatum " ; the capsides are not confined to its apex, but extend half way down the receptacle. S. ricc'upfoHum I have not seen in fruit; it appears, however, identical with H.polyantltos, Sw. (v. Sp. Fil. p. 107.). Whether the H. polyantlios, Hook, and Grev., be that of Swartz, or, as Presl supposed, another species, is difficult to decide, without authentic specimens of Swartz's plant ; it is, however, an excessively common West Indian form, nor does its receptacle differ in any particular from that of several species of Spharocionium ; as from S. sanyuinolention, Presl, (certainly a variety of polyant/ws, Hook, and Grev., if not of Swartz), from some states of demissum and others. S. caiidicidatum : in most of the specimens in Hook. Herb, the short pedicellus is surmounted by a very large depressed sphere covered with capsides, in some indusia this character is very striking, but in others, from the same specimen, it becomes considerably smaller, and in what is manifestly the same plant from other localities the receptacle is simply clavate but very broad. S. dilatation : this very common New Zealand plant is properly retained in the immediate vicinity of demissum ; in no case, however, do I find its receptacle to be globose and incrassated at the apex, it is very like, and varies similarly with, that of the last-named plant. S. crispatum : the receptacle of Indian specimens quite agrees with Presl's character, in some Van Diemen's Land ones that organ is narrower at the summit. <S'. badium, gracile, axillare, and abietinum have the receptacles very short and clavate, or more or less capitate. It is not to be w-ondered at that an organ so variable in the above-mentioned species shoidd afford too frail characters upon which to found a genus ; and a similar examination of some of the plants included in Presl's Hymenophylhon will show that it exists of all lengths, between the long exserted stout column so often seen in H. multifidwm and secundum and the short sessile receptacle of demissum and dilatation ; transition stages, connecting the two genera, are found in both. The limits of Hymenophyllum, as established in the ' Species Filicum,' have been defined after a study of several thousand specimens ; a re-examination of many of which has convinced me that neither can most of the new genera formed out of it remain, nor such sections as that author has proposed under the names of Evoluta and Dimidiata.
Having occasion to describe several species of this genus during the course of publishing the results of the Antarctic Expedition, some apology seems necessary for not adopting Presl's views of the Order Hymenophyllacece. I am fully sensible of the great value of that author's labours and of the accuracy and precision with which he has described what he has examined, as also of his intimate acquaintance with the whole order of Ferns : and whilst I cannot but place some reliance upon the residts of my own observation of far more extensive suites of specimens, in many cases gathered by myself, than Presl has probably had access to, I would further remark, that whilst examining, in the Hookerian herbarium, almost all the species mentioned by Presl, and authentically named specimens of many, I have constantly met wdth abundant evidence of that writer's accuracy in his descriptions of individual species, together with full proof that he has considered some of their peculiarities as of too much im- portance in Systematic Botany.
4. Hymenophyllum flabellatum, Lab.; Fl. Nov. Hott. v. 2. p. 101. t. 250. f. 1. Hook. Sp. Fil. v. 1. p. 111. Presl, Hymenqph. p. 32. H. nitens, Brown Prodr. p. 159. Hook, et Grev. Ic. Fil. 1. 197.
Hab. Lord Auckland's group ; not uncommon on the old and decaying trunks of trees and upon rocks both near the sea and on the lulls.
Of a paler but brighter and more glistening green than the former. A very abundant New Zealand and Tasmanian species, varying a good deal in size and somewhat in the form of the frond.
5. Hymenophyllum rarwm, Br. ; Prodr. p. 159. Hook. Sp. Fil. v. 1. p. 101. H. semibivalve, Hook. et Grev. Ic. Fil. t, 83. Presl, Hymenoph. p. 32.
Far. fi. Hook. Sp. Fil. p. 101.
Hab. Lord Auckland's group ; in woods near the sea, rare.
