NEW FERNS FROM SOUTHERN BRAZIL. 309 



ascribing to the different forms of Festuca such constancy of 

 character as to warrant their being so minutely subdivided and 

 receiving subvarietal names ; also, if there be such constancy, 

 whether every botanist might not add to the number by a careful 

 study of forms in his own neighbourhood, and thus render the 

 accumulation too cumbersome to be of any real practical value. 

 Time only, again, will prove whether future observation and 

 experiment will strengthen or weaken the theory of descent with 

 modification now all but universally accepted, and so ably sup- 

 ported and applied by Prof. Hackel."'^' There can be no doubt of 

 his ability as a patient and able investigator, and his monograph 

 is a valuable contribution to Science. 



About 130 pages are devoted to the descriptive portion of the 

 work. The descriptions of the species, subspecies, and varieties 

 are full, and are drawn up with great care. The synonomy is 

 carefully worked out. The distribution of the forms is given even 

 down to the subvarieties. 



^ 



NEW FERNS FROM SOUTHERN BRAZIL. 

 By J. G. Baker, F.R.S. 



The parcel received lately from Dr. Glaziou, containing the 

 Gurceixia (figured m the August number of this Journal), includes 

 also the following new species of Adiantum, and a very curious new 

 Acrostichum. 



5* AoiANTUM Amelianum, Glaziou in herb. — Stipes slender, 

 tufted, naked, castaneous, 4-6 in. long. Lamina lanceolate, simply 

 pinnate, 6-12 in. long, 18-21 lin. broad, often caudate and rooting 

 at the tip, bright green, membranous, glabrous. Rachis castaneous, 

 without hairs or scales. Pinn« sessile, contiguous, all but the 

 lowest dimidiate, subquadrate, attached by the lowest corner, 

 those at the centre of the frond f-f in. long, entire on the mner 

 and lower borders, deeply lobed on the upper, and finely denticu- 

 late when barren ; basal pinnae suborbicular, with more numerous 

 lobes. Veins fine, close, free, regularly flabellate. Sori one to 

 each lobe of the pinn®, -1-^- in. long, with a moderately broad 

 brown glabrous involucre, G-laziou 12287 ! — A close ally of the 

 very rare A. rhizophytum, Sclirad., figured in Mart. Crypt. Bras., 

 t. 62. 



12''' Adiantum Glaziovii, n. sp. — Rhizome creeping, about the 

 thickness of a swan's quill. Stipes slender, naked, castaneous, y 

 a foot or more long. Lamina deltoid, bipinnate, under a foot long, i/^ 

 bright green, glabrous, firm and rigid in texture ; rachises naked, 

 castaneous. Pinnae 2-5-jugate, erecto-patent, the side ones shorter 

 than the end one, 3-6 in. long, 1-1:^ in. broad. Ultimate segments 

 oblong-deltoid, not contiguous, sessile or subsessile, obtuse, l—f 



* Bull. Soc. Fr., Rev. Bib., 1882, p. 28. 



