94 BURMA, ITS PEOPLE AXD PRODLX'TIOXS. 



Equisetum. is in most cases diojcious. Tiic iirothaUus, which boars Tvell-devehipccl 

 arcliegonia, rarely bears anthcridia as well ; and if archegoniii occur on a proOiullm 

 bearing antheridui, the former are geutrally sterile. 



Order OPHIOGLOSSEJE. 



Fronds straight in vernation. Hporangia globose, coriaceous, bivalved, arranged 

 in a peduncled or sessile spike. ProtliuUus bisexual. 



Opfiioi/hsscre arc separated from true fei'ns by the nature of their rhizome, or Ity 

 their fronds not being rolled uj) in vernation, crozier-fashion, but straight, and 

 by their sporangia being arranged longitudiuallj- on a sort of scape, forming either 

 a sim]>le terminal spike {Ophioglossum) or a raceme [Botri/cliiiim). 



The sporangia have no ring, and contain smooth triangular spores indicating an 

 alliance with Lycopodiacem through Plujlloghsmm. 



Order FILICES. 



Fronds circinnate in vernation, bearing sporangia on their under surface, or 

 margins, or on separate fronds. Prothallus liiscxual. 



Ferns emlirace eight tribes, and, according to some authors, in round numbers, 

 tlirce thousand species. 



MARATTTE.r.. 



Sporangia free, appressed, in 2 roivs, or in a circle or confluent, and iogether 

 resembling a seicral-celled capsule, deprived of rings, each oj/ening hy a slit or pore. 



OSMUNDIE.E. 

 Elastic ring embracing a part of the circumference of the sporangium, or reduced 

 to a small disk of cells with thiclc walls. 



LYGODIE.E. 



Sporangia sessile, ovoid, or turbinate. Elastic ring replaced bg a sort of cap with 

 radiating stria, occupying the end of the sporangium, opposite to the 2)oint of attachment. 



GLEICEENIE^. 



Sporangia solitary, or grouped in definite numbers ("2-3), sessile, globose. Elastic 

 ring perfect, but not corresponding to the jwint of attachment of the sporangium. 



CERA TOPTERIDIE.E. 

 Elastic ring large, formed of vertical cells, not completely surrounding the sporangium, 

 which is sessile. 



STMENOrnYLLIE.E. 

 Elastic rinq oblique and complefeh/ surrounding the sporangium, and on a plane 

 nearly perpendicular to the point of attachment of the sporangium. Sporangia nearly 

 globose. 



CYATMACIEyK. 

 Elastic ring nearly as in Hyinenophyllieie. Sporangium often compressed, sessile, 

 or pedicelled, not continuous with the ring. 



rOLTFODIACIE.K. 

 Elastic ring generally narrow, prolonged from one side of the rather long pedicel, 

 interrupted at the top or the opposite side near the pedicel. 



