Plate 5. 
POLYPODIUM (Piiegoptebis) Bobebtianum, Iloffm. 
Rigid Tliree-branched Polypody. 
Polypodium (Phegopteris) Robertianum; caudex long, creeping, branched, scaly; 
frond rather firm-membranaceous, glandularly pubescent, at length glabrous, 
subpentangularly deltoid or triangular-ovate, tripartito-bipinnate; primary 
pinnae long-petioled (especially the intermediate or terminal one), deltoid- 
ovate ; secondary pinnae mostly sessile, oblong or ovato-oblong, obtuse, 
deeply pinnatifid at the base, and then sometimes again pinnate; segments 
oval-oblong, entire, or the inferior ones pinnatifido-serrate; sori in two rows 
near the margin, dorsal on the vein, often confluent. 
Polypodium Robertianum. G. F. Hoffm. FI. Germ, part 2, 1795, in addend. 
Moore’s Brit. Ferns , Nat. Print, pi. 6. 
Lastrea Robertiana and Gymnocarpium Robertianum. Newm. 
Polypodium calcareum. Smith, FI. Brit. p. 117 (1804); Fngl.Bot.t. 1525. 
Willd. Sp. PI. v. 5. p. 210. Hook, and Am. Brit. FI. ed. 8. p. 581. 
Phegopteris calcarea. Fee , Gen. Fil.p. 243. Metten.Fil. Hort. Lips.p. 83. 
Phegopt.p. 9. 
Polypodium Dryopteris. Dicks, dr. Plant, t. 16; and Bolt. Fil.p. 53. t. 1 ( ac - 
cording to Sir Jas. Smith ; and of American authors , according to Mr. Moore). 
Benth. Handb. of Brit. FI. p. 626.— f3. Wahl. FI. Suec. v. 2. p. 668. 
Hab. Limestone debris, chiefly in the northern and western parts of England. 
Our most authentic specimens are from Matlock, Derbyshire, Sir J. F. Smith. 
This graceful Fern, which has so many points in common with 
our preceding species {Pol. Dryopteris ), was first distinguished 
from it by Hoffmann, in his little ‘ Flora of Germany/ a work 
unknown to Sir Jas. E. Smith, and probably to many other 
botanists, and hence he and subsequent writers have not main¬ 
tained the original name, till lately, when Mr. Newman and Mr. 
Moore adopted the oldest. It is, however, not a little re¬ 
markable that neither of the first describers in their specific 
character, indicates any good mark by which it can be distin¬ 
guished from Pol. Dryopteris. Take Hoffmann’s character, for 
example: “ Fronde triangulari, foliolis ternis bipinnatis, pinnis 
pinnulisque inferne pinnatifidis/’ or Smith’s: “Fronde ternata, 
bipinnata, ereeta, rigidula; laciniis obtusis subcrenatis, maculis 
fructiferis confluentibus.” It is true Hoffmann, in his remarks, 
adds, what is now considered the most dependable mark, “ frons 
uterque nudo oculo subtili tomento, ad lentem brevissimis glan- 
dulis obsitaand “ odor debilis Geranii Uobertiani ” (whence, 
of course, his specific name). Smith takes no notice of the 
glandular pubescence, not even in his subsequent publications, 
nor is it represented in the ‘ English Botany ’ figure,—and 
