346 



THE BOOK OF CHOICE FERNS. 



and at the base shaggy with rust-coloured scales, l^in. long, and fine hairs ; 

 the leafy portion of the fronds is large, thick, black above, chocolate- coloured 

 beneath, and clothed with tawny hairs of a woolly nature. Their pinnas 

 (leaflets), 1ft. or more long, are furnished with pinnules (leafits) 2in. to 2 Jin. 

 long and ^in. broad, whose oblong and very obtuse lobes are entire. The 

 rust-coloured son (spore masses) are disposed chiefly on the lower half of 

 the lobes close to their midrib. — llooher and Baker, Synopsis Filicum, p. 38. 



A. atrovirens — a'-tro-vir'-ens (dark green), Presl. 



A gigantic-growing species, native of South Brazil. Its large fronds, 

 tripinnatifid (three times divided half-way to the midrib), are borne on stipes 

 (stalks) about equal in length to their leafy portion (Fig. 52), stout and 

 slightly scaly. Their rachis (stalk of the leafy portion), of a dark straw- 

 colour, sometimes perfectly smooth, at other times slightly muricated (rough, 

 with short, hard excrescences), is furnished with spear-shaped pinna) (leaflets) 

 9 in. to loin, long and 3in. to 4in. broad ; the pinnules (leafits), cut about 

 half-way down to the midrib, are .nearly stalkless, of a sub- coriaceous (almost 

 leathery) texture, dark green on both sides, and without scales ; their 

 ascending and entire segments are Jin. broad, and blunt. The small and 

 numerous sori (spare masses) are medial (set on the forking of the veins, 

 but close to the midrib). — Hooker, Species Filicum, i., p. 46. 



A. aus trails — aus-tra'-lis (Southern), Brown. 



This noble, greenhouse species, native of Tasmania and Australia, 

 especially in the South, is undoubtedly one of the handsomest Alsophilas 

 in cultivation. It is also probably one of the best-known arborescent kinds, 

 forming generally a very straight stem or trunk of great height and well 

 proportioned — neither too slender nor too bulky in appearance. A trunk of 

 15ft. or 18ft. high generally measures from 2ft. to 2jft, in circumference, 

 and produces a somewhat flat or spreading head of numerous fronds, 8ft. to 

 13ft. long and borne on naked stipes (stalks) about ljft. long. Their 

 primary pinna? (principal leaflets), spear-shaped, about ljffc. long and 6in. 

 to lOin. broad, are furnished with numerous pinnules (leafits), light green 

 above and glaucous (bluish) below, 3in. to 4in. long, acuminate (sharply 

 pointed), and deeply pinnatifid (divided nearly to their midrib), or towards 



