Victorian Plants. 517 



Frond-segments dimidiate-rhomboid, almost sessile ... 2157 



2157. Cover of fruit-masses elliptic-renate, placed on the 



denticles, thus almost exserted. 



Tall ; fronds quite large, repeatedly pinnate, almost deltoid 

 in outline ; stalk and rhaches very dark and shining, 

 somewhat rough ; rhaches of the ultimate pinnules beset 

 with minute hairlets ; segments thin, numerous, alterna- 

 ting, regularly bi-seriated, slightly indented along the 

 upper margin ; venulation close, dichotomous. 



A. formostiin. 



Cover of fruit-masses broad-renate, placed between 

 the denticles, thus almost retracted. 



Dwarf; very scantily beset with bristlets, otherwise glabrous; 

 stalk and rhaches very dark and shining ; fronds generally 

 consisting of few crowded pinnas only ; segments very thin, 

 closely alternating, usually blunt, regularly biseriated, in 

 front shortly indented ; fruit-covers overtopped by the 

 denticles of the segments. A. diapliamim. 



LINDSAYA. 



2158. Fronds very narrow in outline, simply pinnate. 



Dwarf ; root-stock creeping ; rootlets rather copious ; stalks 

 very thin, as well as the rhaches dark and shining ; some 

 of the fronds sterile ; segments quite small, mostly 

 opposite, sessile, from cuneate to rhomboid and flabellular, 

 often inequilateral ; fruit-cover narrow, extending along 

 the terminal margin of the frond -segments ; spore-caselets 

 on conspicuous stalklets. Figure 141. 3J. linearis. 



PTERIS. 



2159. Fronds simply pinnate or imperfectly bipinnate ... 2160 



Fronds repeatedly pinnate ... ... ... ... 2162 



2160. Frond-segments decurrent and adnate at the base. 



Tall; fronds rather membranous, dark-green, often bi-pinnate 

 in its lower portion ; segments very long, from linear- to 

 narrow-lanceolar, mostly opposite, very acute, the upper 

 half of each narrowed at the base quite to the carinular 

 line, minutely serrulated towards the summit ; lateral 

 venules almost parallel-spreading; spore-caselets placed 

 on a filiform-linear axis. P. nmbrosa. 



Fronds segments truncate and free at the base ... 2161 



