364 CHARACTERS OP TRIBES AND GENERA. 



fronds). Fronds bi-tripinnate, 6 to 8 or more feet high ; pinnse 

 and pinnules articulated with the rachis. Veins simple or 

 forked, free. Sporangia sub-terminal, connate, forming a 

 bivalved synangium, each valve consisting of 3 to 12 cells, 

 opening by slits. Receptacles ovate, oblong, some species 

 furnished with an indusoid fimbriate membrane. 



Type. Marattia alata, 8m. 



Illust. Hook, and Bauer Gen. Fil., t. 26; Moore Ind. 

 Fil., p. 96 B. ; J. Sm. Ferns, Brit, and For., fig. 150 ; 

 Hook. Syn. Fil., t. 9, fig. 70. 



OBS. The general habit and mode of development of 

 the fronds of this genus does not differ from Angiopteris, it 

 is, however, readily distinguished by its sporangia being 

 wholly united, the two series forming a double multilocular 

 spore case, which, when mature, opens lengthways in two 

 lobes (valves), each lobe containing a series of cells equiva- 

 lent to the sporangia of Angiopteris. Marattia is sparingly 

 represented in India, but it is common to the Islands of the 

 Indian and Pacific Oceans, extending to Norfolk Island and 

 New Zealand in the South, it is also found in South Africa, 

 Tropical America, the West Indian Islands, and is one of 

 the few plants forming the indigenous flora of the Island 

 of Ascension. 



Presl enumerates twenty species, which he places under 

 four distinct genera, but I find no sufficient character to 

 warrant their adoption, his species are also fully double in 

 excess. In the " Species Filicum " only seven species are 

 described, and the following, which have all been cultivated 

 at Kew, appear to me to have sufficient character to be 

 considered distinct species. Different fronds, or even dif- 

 ferent parts of the frond of the same plant when separate, 

 and placed in the herbarium, have been accepted as at 

 least four distinct species. 



