c . GENEKA OF FERNS: 



on the anterior lower venules. Involucre firm membranaceous 

 or sub-coriaceous, sessile, attached by a small point, globose, 

 entire, at length bursting and splitting irregularly from the top. 

 Veins simple forked or (in the secondary pinnules) pinnate ; 

 venules simple, free. 



Fronds decompound, herbaceous. Ehizome short, erect ? 

 The chief peculiarity in this genus is the hard globose entirely 

 closed involucres, which at length burst open irregularly, and are 

 affixed by a small point of contact. These characters separate it 

 not too definitely perhaps from Woodsia ; while from Per ci- 

 nema, on the other hand, it is distinguished by the sessile instead 

 of stalked globose involucres. 



Ex.: D. aspidioides, SI. \ D. pseudo-esenopteris, Kze. 



D. madagascariensis, me. \ D. microphylla (Cyathea, Mett.) 



141. (?) ARACHMTODES, Slume, Enum. PI. Jav. 241. 



Sori involucrate, " roundish, scattered, inserted upon a slightly 

 elevated receptacle. Involucre arachnoid, covering the sorus." 



Cm.) 



" Involucre a cobweb-like substance, so tender as scarcely to 

 be called a membrane, covering each sorus." Blume compares 

 his plant with Aspidium as to habit, and with Chnoophora and 

 Trichopteris as to its fructification. Hooker associates it doubt- 

 fully with Diacalpe and Woodsia. Fee places it without doubt, 

 with AlsopJiila. We cannot, from the evidence we possess, 

 form any decided opinion where it ought to be placed ; but we 

 may presume that it possibly belongs here, as Blume puts it in a 

 section " indusia soris subjecta," and places it next to Diacalpe, 



Ex.: A. aspidioides, SI. 



142. WOODSIA, E. Brown, Trans. Lm. Soo. xi. 173. 1. 11 ; 



(Woodia, Sr. Prod. 158, in obs.) 



PHYSBMATITJM, Eaulfus; HYMBWOCYSTIS, C.A.ateyer; HYMENOL.KNA, 

 C.A.Meyer; PKBBINIA, Hooker; POLYPODII sp., Auct. ; ASPIDII sp., 

 Auct.; ALSOPHILS sp.,Auct.; DICKSOITIJ! sp.,Auct.; CYSTOPTEEID* 

 sp., Auct.; LASTSB^ sp.,Pre*Z; ACEOSTICHI sp., Auct. ; CETEBACHIS 

 sp., Auct.; NOTHOCHL^H^ sp., Desvaux. 



Sori involucrate i.e. with inferior indusia, globose; the 



