POLYPODIACEAE 11 



V. ADIAXTEAE 



Leaves pinnately or pedately com- 

 pound, the leaflets very oblique. 7. ADIAXTCM. 



VI. BLECHXEAE 



Blades of the leaflets or leaf-seg- 

 ments entire or toothed : veins 

 free, or in spore-bearing leaflets 

 connected near their bases by a 

 transverse continuous receptacle : 

 sori continuous or nearly so. 8. BLECHXUM. 



Blades of the leaflets pinnatifid : 

 veins anastomosing near the mid- 

 rib : sori Interrupted, chain-like. 9. ANCHISTEA. 



VII. DRYOPTERIDEAE. 



Veins copiously and irregularly an- 

 astomosing, the areolae irregular : 

 sori separated. 10. TECTARIA, 



Veins free or those of the lower one 

 or two pairs joined and running 

 to the sinus. 11. DHYOPTERIS. 



VIII. XEPHROLEPIDIAE 

 Epiphytic or terrestrial plants : 

 leaves long and narrow, often 

 greatly elongate : leaflets numer- 

 ous ; blades toothed : indusia reni- 

 form or orbicular-reniform. 12. NEPHROLEPIS. 



1. ACROSTICHTTM L. 



Tall coarse marsh-plants or swamp-plants. Leaves 

 on the short or somewhat elongate rootstock: petioles 

 smooth or with several pairs of spur-like spines: blades 

 pinnate, on stout petioles; leaflets leathery, the blades 

 thick, entire or obscurely toothed, flat, erect or spread- 

 ing. Veins anastomosing, forming copious minute are- 

 olae without free veinlets. Sporangia very numerous, 

 thickly covering the entire lower surface of all the leaf- 

 lets or of the upper leaflets only, with a red or brown 

 felt-like coating. About five species, widely distributed 

 in the tropics. A species, A. aiireum, additional to the 

 following, occurs in the nearby coastal region. 



