CHARACTERS OF TRIBES AND GENERA. 363 



countries of the eastern hemisphere and islands of the 

 Pacific, the numerous localities presenting different phases 

 of what some authors suppose to be one species only, while 

 De Vriese describes no less than sixty species. On judging 

 from my examination of authentic specimens from De 

 Yriese, in the Hookerian herbarium, I have no hesitation 

 in saying they may be safely reduced to one- sixth of that 

 number, indeed in the " Synopsis Filicum " the whole are 

 reduced to one species, namely, the original type, A. evecta. 

 Judging from the aspect, and some special differences of 

 cultivated plants, I consider the following as distinct 

 species. The chief difference besides the aspects consists 

 in the number of sporangia forming the sorus, which 

 varies from a few to many ; these numbers appear to be 

 constant and uniform in individual plants, but the various 

 intermediate numbers observed in others destroys the well 

 marked difference between the lesser and greater numbers. 

 In some a narrow fimbriate membrane is observed under 

 the sporangia, which is considered to represent an in- 

 dusium. 



Sp. A. evecta, Ho/m. (v v.) ; A. Teysmanniana, De 

 Vriese (v v.) ; A. Brongniartiana, De Vriese (v v.) ; A. 

 pruinosa, Kze. (v v.) ; A. hypoleuca, De Vriese (v v.) ; A. 

 Miqueliana, De Vriese (v v.). 



OBS. In Sikkim a plant of A. evecta has been measured 

 having a caudex 2 feet 4 inches high and 2 feet 6 inches in 

 diameter, the spread of fronds being 24 feet, being ten less 

 than a plant cultivated at Kew. 



214. MARATTIA, Sm. (1793). 



Vernation fasciculate, erect, sub-arboroid ; each frond 

 rising from between two fleshy stipulaeform appendages 

 (which sometimes assume the character of abnormal 



