Ahophila.] CLVI. FILICE8. I949 



8. A. excelsa (tall), R. Br. Prod. ; Hook. Sp. Fil. i. 49. Common Fern-tree. 

 Stems stout, the average height from 12 to 30ffc. The frond large bipinnate, the 

 stipes and main rhaohis more or less muricate, and when young bearing chaffy 

 scales mixed with wool ; pinnules oblong-lanceolate acuminate, segments oblong 

 rather acute, sometimes serrate at length coriaceous with the margins reflexed, 

 the lower ones sub-auriculate at the base free and even slightly petiolate, the 

 lower half or sometimes the whole segment bearing sori ; veins often twice or 

 thrice forked, spore-cases mixed with hairs.— Hook. I.e. tab. xviii A. • Bail Litho 

 Ferns Ql. 85 and 36. 



Hab.: Comnion in coastal scrubs. 



4. A. australis (Australian), R. Br. Prod. ; Hook. Sp. Fil. i. 50. Common 

 Fern-tree. Stems as tall but not so stout as A. excelsa. The fronds similar to 

 the last-mentioned but smaller in all their parts, the segments more acute. Sori 

 1 to 4 on the lower part of the segment ; veins simple and forked, the spore- 

 cases mixed with a few hairs. — Hook. I.e. xix. A. ; Bail. Litho. Ferns Ql. 84 and 

 37. 



Hab.; Common in coastal scrubs. 



The species A. excelsa and A. australis scarcely differ from each other in anything but size, 

 however, I think it will be found most convenient to retain them as distinct species and allow 

 all the intermediate species and varieties which have been published from time to time to lapse, 

 as all such seem to have only been conditions of growth. 



5. A. Iieichhardtiana (after L. Leichhardt), F. v. M. Fragm. v. 53, 117. 

 Benth. t<l. Austr. vii. 711. Prickly Fern-tree. Trunk from 10 to 20ft. high, 

 slender, hard and dark. Fronds large spreading, rhachis dark, rough or 

 mueronate-spinulose, loosely tomentose or quite glabrous ; ultimate pinnules more 

 detached narrower and more serrate. Sori small, in very distinct series close to 

 the midrib. Base of the stipes often covered with long brown setaceous hairs 

 without the flattened scales of A. australis. — Hook, and Bak. Syn. Filic. ed. 2, 

 40 ; Bail. Litho. Ferns Ql. 38; A. Macarthurii, Hook. I.e. ed. 1. 40. 



Hab.: Common in coastal scrubs. 



6. A. Robertsiana (after William George Boberts), F. v. M. hragin. v. 54, 

 117 ; Benth. Fl. Austr. vii. 712. Trunk smooth, 10 to 12ft. high, 2 to 4in. 

 diameter, elongated beyond the last frond. Fronds not forming a crown, but are 

 somewhat distantly placed on the stem ; bipinnate, the rhachis both general and 

 partial as well as the pinnules themselves and sori hispid or sprinkled with rigid 

 hairs. Secondary pinnae 2 to Sin. long. Pinnules distinct, 4 to 6 linss long, 

 deeply pinnatifid, the upper ones of each pinna smaller, more entire and 

 confluent. Sori rather large, solitary opposite each lobe of the pinnule. — 

 Hook, and Bak. Syn. Filic. 459 ; Bail. Litho. Ferns Ql. 89. 



Hab.: Eockingham Bay, Dallachy ; Bellenden-Ker Range, W. Hill and Bailey. 



16. DICKSONIA, L'Her. 



(After James Diekson, a British cryptogamist.) 



Trunk arborescent or rhizome creeping. Fronds large, compound. Pinnules 



penniveined. Sori terminating veins close to the margins of the frond. Indusium 



either globular and 2-valved or cup-shaped and entire, the upper valve or upper 



part of the eup adnate to the frond and continuous with the margin. 



The genus extends over the tropical and subtropical regions of the New and the Old World. 



Sori on the concave lobes of the pinnules, which are closely adnate to and 

 form the greater part of the upper valve of the indusium. Trees. 



Indusium about 4 line diameter • . . 1. D. antarctica. 



Indusium about 1 line diameter • . 2. D. Youngite. 



Sori under the sinus or at the inner base of the lobes of the pinnules. 



Indusium cup-shaped. Bhizome creeping . , , , . S. D. davalUoides, 



Pabt VI. Bfll 



