— 58 — 



When using my key it should be born in mind: 



That the fronds of some species are very large and may reach a 

 length of more than 6 meter; 



That the pinnae collected are not always those having the largest 

 pinnulae and that the dimensions given in the diagnoses commonly are 

 those of the largest pinnulae available to the individual authors; 



That the noted colour of rachises, pinnulae, costae and veins and the 

 degree of transparency of the veins and venules are taken as a rule from 

 dried material which often shows in the same frond, even in the same 

 pinnula, absolutely opposite characteristics; 



That the recurrent venules, apparently wanting when seen in reflected 

 light, may be distinctly visible when examined towards the light. 



{ could not entirely avoid mentioning in the key characteristics which 

 may be different in the same specimen; they are to be considered as 

 approximate for the normal condition. — F.i.: if one may have found only 

 one pale-coloured pinnula with pale veins among many others of the same 

 frond, which are dark, then the dark colour is to be considered as 

 representing the normal condition. 



a. Pinnulae beneath prninose or waxy. 



b. Largest pinnulae at best 2 cm. broad. - 

 c. Rachises at length black-verruculose by the persistent bases of 

 fallen scales. (1) A- crinita. 



cc. Rachises smooth, at least not black-verruculose when destitute 

 of the indumentum. 



d. Sori separated from the margin by a space broader than the 

 line of sori. (2) A. glauca. 



dd. Sori separated from the margin by a space narrower than 

 the line of sori. 



e. Indusium wanting or hardly distinguishable. (3) A. leytensis. 

 ee. Indusium distinct, consisting of proportionally long hairs or 

 ' fibres. 



f. Pinnulae entire or subentire, at best obsoletely crenulate. 



(4) A. Forbesii. 



//. Pinnulae distinctly crenulate, serrulate or denticulate. 



(5) A. pruinosa. 



bb. Largest pinnulae at least 2 cm. broad. 



c. Pinnulae at best 5 times as long as broad. (6) A. hypoleuca. 

 cc. Pinnulae at least 5 times as long as broad. (1) A. ceracea. 

 aa. Pinnulae beneath not pruinose or waxy though not rarely minutely 

 pale-punctulate. 



t 



