iiyi'oi)i;kius. 57 



lion, bring together plants very little allied hy nature, for no Ferns can be 

 more different, if habit be considered, than Ilypoderris and Trichmnanes ; 

 yet if the nature of the sori and of the involucre especially is of such prima- 

 ry importance as has generally been allowed, I have no other characters 

 to offer, and none so sim])le, as the usually free cup-ahnped snmelhnrs bifid 

 involucre of Dicksmiiva;. Loxsnuia, while it is closely allied in the form 

 and structure of the involucre to Trichomanes on the one hand, on the otlier 

 is the connecting link with DavulUea;. 



SuBTRiBE I. Sori on (he junction of reticulated veins or veinlets. 

 Hypoderkidk.'e. 



1. Hypoderris, Br. 

 Sori dorsal, globose, inserted in lines or series, parallel with 

 the primary veins upon the confluent angles of reticulated 

 veinlets. Involucre inferior calyciform thin and membrana- 

 ceous loosely reticulated, the margin spreading and fimbria- 

 ted. C^/?.s;//c.s nearly globose, stipitate, on a small punctiform 

 receptacle. — Nat ire o/ Trinidad. Frond stipitate, si))) pie, 

 siihcordato-Jinstate, acmninate, costate, pi))))atedly rei))ed, 

 7j)e)))hranaceoiis ; veins alternate, nearly parallel, Jlex)iose; 

 primary veinlets pinnated, the rest anastomosing, so that 

 almost the ivhole surface has a reticulated venation. Hook. 

 Gen. Fil. Tab. 1. 



1. H. Brownii. J. Stn. MS. in Hook. Gen. Fil. I. c. Hook. 

 Jc. PI. t. 675, 676. 



Hab. St. Anne's Valley, Trinidad, Lockhart. — Caudex creeping. Stipes 

 from a span to a foot high, scaly. Frond longer than the stipes, ovate -lan- 

 ceolate, acuminate, entire, membranaceous, glabrous, the base with rather 

 a deep sinus, and on each side a short obtuse rounded lobe, or this is occa- 

 sionally prolonged into two broadly lanceolate, sometimes acuminated, erecto- 

 palent segments, 2 — 5 inches long. Costa strong, emitting a branch at 

 the base to each auriculated segment; this costa is again regularly pinnated 

 with strong, parallel veins, which are connected by slender transverse ones, 

 sending off branches which form a nearly hexangular, delicate network over 

 the whole surface. Several of the areohT, especially near the strong lateral 

 veins from the costa, are occupied by a free veinlet. Sori not very copious 

 and always on the angle of united veinlets arranged in rather remote series 

 on each side of the lateral veins just mentioned ; and when more copious 

 also on each side the primary transverse veinlets. 



This rare i)Iaut was lirst noticed by Mr. Brown, who says, in Wallich's 

 Ic. Plant. Asiat. Rar., when speaking of Malonia, " the beautiful ramifica- 

 tion of veins in Matonia, is not altogelhcr peculiar to it. Among the ge- 

 nera of Poh/podiacecB having an indusium, one remarkable example occurs 

 in a genus yet uiidescribcd (Ili/podcrris), which, with an indusium not ma- 

 terially different from that of IVoodsia, has exactly the habit of Aspidiiiin 

 trifnliatum, while of those genera of Poli/podiacicE which arc without an in- 

 dusium, the same kind of vascularity is iound in an cxttnsivc and very na- 

 tural section of Polypodium, to which P. Pln/malodes and the greater num- 

 ber of those species, 'sori saccati' belong.'' — Mr. J. Smith places this genus 

 in ^^Aspidiets" between Matonia and Aspidium,Pr. although its involucre is 



