PTERIS AQUILINA. Common Brake. Braken. Eagle Fern. 

 TAB. XXXVIII. 



Fronds deltoid, with an elongated stem-like petiole, bi-tripinnate ; 

 primary pinnae opposite ; ultimate segments oblong, obtuse. 



Pteris aquilina, Linnceus. Smith. E. B. 1679. Hooker and Arnott. 

 Babington. Moore. Eupteris aquilina, Newman, Hist. Brit. 

 Ferns, 23. 



Abundant on heaths and moors, and on stony and sandy pastures, 

 as well as in woods and thickets, throughout the kingdom. The 

 rhizoma, of a dark colour and velvety exterior, extends far below 

 the soil, branching and creeping in every direction, so as to form, 

 where long established, a densely interwoven horizontal network at 

 a greater or less distance below the surface, according to the cha- 

 racter of the subsoil. It has often been observed that the plant is 

 not found over chalk, a circumstance, however, apparently due 

 rather to the ordinary shallowness of the soil over that rock in 

 England, than to any prejudicial influence of the chalk itself. The 

 repeatedly compound fronds grow upward, at intervals, to the 

 height of from six inches to eight or nine feet, according to the 

 fertility of the spot, or as they are more or less exposed or sheltered ; 

 in a moist wood, near Hampstead-heath, I once measured one up- 

 wards of thirteen feet long; such inordinate growth is rarely 

 attended with the production of fruit. The stem-like portion of 

 the rachis is light yellowish-green, passing into a purplish-brown 

 or black at the lower part ; the leafy part of the frond deep green, 

 and smooth on the upper surface, pale and hairy beneath. The 

 compound character varies according to size and other circum- 

 stances ; the primary pinnae, usually opposite, are generally broad, 

 the secondary ones narrow or linear-lanceolate ; the pinnules, or ulti- 

 mate divisions, are sessile, always confluent towards the extremity, 

 oblong and obtuse. Owing to the peculiar disposition of the woody 

 tissue and its dark hue, a transverse section of the lower end of the 

 rachis presents a fanciful image of an oak-tree, or, if cut obliquely, 

 of the imperial or spread-eagle; in either case it is a pretty object 

 for the microscope. The fronds appear above ground in May, but 

 are liable to be destroyed by very slight frost before they have un- 

 folded, and, when mature, are always among the first natural objects 

 whose change of appearance indicates the approach of winter. 



No permanent varieties occur of this most common fern, though 

 it is liable to considerable modification in different localities. It is 

 seldom cultivated, on account of its tendency to overrun other 

 species, a vagrant habit that is difficult to control. Some trouble 

 and frequent disappointment may be incurred in the endeavour to 

 establish it, either in pots or in the garden, on account of the depth 



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