PlEUEOaBAMMEiE. XXTU. 



lines of spore-cases become oonfluent. Veins reduced to the 

 eosta, and the intramarginal receptacles parallel with it. 



IFrouds crowded, simple, narrow, erect. Bhizome short, creep- 

 ing. — This fern has been placed by its author near to Blechmim. 

 The firactification, however, as indicated ia the admirable figure 

 above quoted, does not appear to us to have any affinity with 

 Blechwum. The spore-cases lie in two deep oblique furrows, one 

 on each side the costa and open towards it ; but the upper valve 

 of this farrow is thick and herbaceous and not of the nature of 

 an indusium. The furrows are rather analogous to what occurs 

 in VittcinecB, only they are in a different position. The plant 

 appears to us to associate better with the Flem'ogrcm/metB. 

 Ex. ; D. angustissima, Srackenridge. 



(c) Veins simple, oblique, from a central costa. 



24. PLETJEO GRAMMA, Blvme, Fl. Jm. 69 (§) : Iresl, 



Tent. Fter. 223. 



CoCHiiDii sp., KaulfuBs; MiCEOPTEEiDiB sp., Beavaux: Tjenitidis ep., 

 Kau^uss; Bleohiti sp., Willdenow; Geammitidis Bp., Auct.; MoKO- 

 GBAMMATIS Bp., Auct. 



Sori superficial, non-indusiate, more or less elongate near the 

 apex of the frond ; the receptacle contiguous to, or more or less 

 coalescent with the costa. Veins simple or forked irom a central 

 costa, free. 



Fronds small, entire, linear, rarely ovoid. Rhizome creeping. 



Ex. : P. graminifolia^ Fresl. I P. linearis, Tresl. 



P. pumila, Fresl. [ P. linearlfolia (Monogramma, Deav.J 



25. XIPHOPTEEIS, Kaulfass, Serlim JaUh. der Ph.— ; 



Id. JEmm. Ml. 85. 



MicEOPTEEiDis sp., jDesvaua: ; Geammitidis Bp., -iMcf j Aceobtichi sp., 

 SwaHz; AspLEirii sy,,SwaHz; Gtmnoptebidis sp., .FerwAcwdi ; Polt- 

 PODU sp., JHetteniiMs. 



Sori superficial, non-indusiate, elongate on the dilated and 

 longitudinally plicate apex of the fronds; the receptacle co- 

 alescent with the eosta. Veins simple from a central costa, free. 



