522 Key to the System of 



2175. Cover of fruit-masses tumid. 



Tall, finally developing a real though never tall trunk ; 

 fronds long-stalked, flaccid, sometimes very large, re- 

 peatedly pinnate, somewhat deltoid in outline ; segments 

 almost ovate-semilanceolar, the upper confluent, slightly 

 or distinctly denticulated, occasionally incised ; fruit- 

 masses rather short ; fruit-cover almost ellipsoid, at first 

 closed by its margin meeting from each side contiguously 

 beneath, soon anteriorely but often irregularly dehiscent. 



A. umbrosum. 



Cover of fruit-masses depressed 



2176. Comparatively dwarf. 



Sub-alpine, tufted ; fronds small, on slender stalks, firm, 

 bi-pinnate when well developed ; segments often somewhat 

 scattered, from roundish- to ovate-rhomboid or occasionally 

 cuneate, oblique, mostly very narrowed at the base, incised 

 or indented in front; fruit -masses seldom more than three 

 to any of the segments. A. Hookerianum. 



Comparatively tall 



2177. Fruit-masses almost marginal. 



Often on trunks of fern-trees, somewhat pendent ; fronds 

 of very thick texture, even sometimes almost carnulent, 

 often only imperfectly bi-pinnate ; pinnules elongated, 

 much narrowed upwards ; lobes of segments from lanceo- 

 late-linear to semi-lanceolar, the lower slightly distant, 

 the upper confluent ; fruit-masses broadish ; spore-case- 

 lets on conspicuous stalklets. A, flacciduni, 



Fruit-masses quite dorsal. 



Somewhat beset with pointed narrow scalelets ; fronds 

 rather flaccid, bi-pinnate, often generating proliferously 

 some young plants from near the summit ; pinnas mostly 

 alternate, almost semi-lanceolar in outline, pointed ; 

 segments from rhomboid- to elliptic-ovate, somewhat 

 decurrent, indented ; fruit-masses rather broadish. 



A. bulbiferum. 



2178. Segments of fronds quite long. 



Usually also here a coast-fern, robust but never tall, occa- 

 sionally quite dwarfed ; fronds conspicuously stalked, of 

 very thick texture, almost lanceolar in outline ; segments 

 elliptic- or lanceolar-ovate, slightly acute or oftener blunt, 

 rather obtusely denticulated, seldom somewhat incised, 

 very narrowed only at the base, occasionally reduced to 

 very few ; fruit-masses comparatively large and often 

 especially long. A. marinuni. 



