POLYPODIACEAE 



25 





scales: leaves mostly 1 m. 

 tall or less; petioles light- 

 brown or dark-brown, some- 

 what shining, with decidu- 

 ous scales, particularly near 

 the base; blades dark-green, 

 hastate, 1.5-5 dm. long, 

 somewhat leathery, undivided 

 or 3-5-f oliolate ; leaflets va- 

 rious, the terminal one the 

 largest, the blades acumi- 

 nate, undulate, incised, or 

 lobed,. those of the lower 

 pair stalked, more or less 

 curved: sori numerous, in 

 two rows between the lateral 

 veins, about 2-2.5 mm. in 

 diameter: indusia orbicular, 

 peltate. (HALBERD-FERN.) 

 Hammocks. Figure 14, 

 reduced. 



This large halberd-fern is 

 most at home in the pro- 

 longed twilight of the very 

 dense hammock. It thrives 

 best in habitats suitable to 

 the growth of the maiden- 

 hair (Adiantum tenerum) and usually in company with 

 it. It grows in- and on the edges of shallow lime-sinks, 

 sometimes almost carpeting the hammock floor, and is 

 largest in the well-like lime-sinks of some of the pineland 

 hammocks, particularly in the smaller sinks, where it 

 often grows a foot or two below the orifice with the 

 large leaf-blades supported on the elongate petioles, 

 completely hiding the sink, thus forming a perfect pit- 

 fall. The plants do not reach their best development 

 in Eoyal Palm Hammock and occur there rather spar- 

 ingly. 



It was discovered in Florida in 1880, in the upper 



