274 



HART S-TONGUE SPLEENWORT. 



become horizontal, and at last pendulous ; they arrive at ma- 

 turity by the end of September, and continue in full vigour 

 throughout the winter, and until those of the ensuing year 

 make their appearance. The form of the 

 frond is elongate, linear, and quite undi- 

 vided, acute at the apex and cordate at 

 the base : the stipes varies from a fifth to 

 a third of the entire length of the frond ; 

 it is of a dark purple colour, and rather 

 scaly at the base : in some specimens, 

 but these are generally young, the entire 

 plant is hirsute, in others perfectly gla- 

 brous. The seedling plants put on a va- 

 riety of forms ; a few of them are sho^vn 

 in the margin. The veins proceed di- 

 rectly from the rachis, and each has four 

 or five branches : to the outside branches 

 of each vein, or system of veins, is at- 

 tached a long line of capsules, covered 

 by a white membranous involucre of the 

 same form : owing to this disposition of 

 the capsules on the outer branch of each 

 sj^stem of veins, the masses are invariably 

 in pairs ; the two involucres at first meet, 

 and appear as one ; a day or two later a 

 line appears between them, showing that 

 they are divided ; the line gradually be- 

 comes more apparent as the capsules in- 

 crease in size ; at last, the two involucres 

 are pushed back from each other, and 

 finally disappear. The veins and attach- 

 ment of the capsules are shown on the 

 upper side of the figure at page 275 ; the 

 involucres and clusters of capsules on the 

 lower side : the earliest stage of the dou- 

 ble line and its involucre is shown to the 

 left hand, and each successive figure towards the right shows a 

 gradual advance to maturity. I have taken great pains to make 

 myself understood as to the distinctive character of this genus, 

 not merely for the sake of mj' own work, but because it appears 



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