206 



THE BOOK OF CHOICE FERNS. 



Settle, in Yorkshire ; at Arncliff, Gordale, and White Scars, near Ingleton ; at 

 Shedding Clough, near Burnley, and near Lancaster ; in Leigh Woods, near 

 Bristol ; and on Cheddar Cliffs and Box Quarries, near Bath, in Somersetshire. 

 Although the plant was only first recognised as a native of England by the 

 late Sir E. Smith, formerly President of the Linnean Society, the " Limestone 

 Polypody" was known to such old authors as Clusius Tabernaemontanus, and 

 in Johnson's edition of Gerarde's "Herbal" it is figured and described as 

 Dryopteris Tragi. P. calcareum is another name for this species. 



The fronds of P. Robertianum are distinctly bipinnate, with the lowest 

 pair of leaflets occasionally twice cleft again on the posterior side ; they are 

 6in. to 18in. long, somewhat rigid, upright, and produced from a creeping 

 rhizome of a dark brown colour. The small, round sori (spore masses) are 

 scattered over the whole under- surface, where they become partially confluent. 

 — Hooker, British Ferns, t. 5. T. Moore, Ferns of Great Britain and 

 Ireland, t. 6. Lowe, Ferns British and Exotic, i., t. 28. Correvon, Les 

 Fougeres rustiques, p. 149. Lowe, Our Native Ferns, i., t. 5. 



P. (Phymatodes) rostratum— Phy- 



mat-o'-des ; ros-tra'-tum (beaked), 

 Hooker. 

 A small-growing, greenhouse species, 

 native of Khasya, Bhotan, and Mishmee, 

 in the Eastern Himalayas. Its entire (un- 

 divided) fronds, 2in. to 4in. long, Jin. to 

 lin. broad, and borne on firm, naked stalks 

 lin. to 2in. long, are produced from a 

 thread-like, wide-creeping rhizome clothed 

 with narrow scales. They are gradually 

 narrowed to both ends, and have their edge entire ; their texture is 

 leathery, and the large sori (spore masses) are disposed in single rows 

 near the midrib. This Fern delights in decomposed vegetable matter, and 

 makes a pretty specimen when grown on a Tree-Fern trunk. Fig. 59 is 

 reduced from Col, Beddome's " Ferns of British India," by the kind 

 permission of the author.— Hooker, Species Filicum, v., p. 66 ; Second 

 Century of Ferns, t. 53. Beddome, Ferns of British India, t. 159. 



Fig, 59, Polypodium rostratum 

 (\ nat. size). 



