BRITISH FERNS. 43 



ALPINE PRICKLY FERN. 

 POLYSTICHUM LONCHITIS. All the authorities are doubtful. 



LOCALITIES. 



ENGLAND. ") 



WALES. \ Not decidedly ascertained. 



SCOTLAND, j 



IRELAND. . . County Donegal, Rosses and Thanet Mountain Pass ; County Sligo, Ben Bulben. 



UNTIL my late visit to Ireland, I felt perfectly convinced that 

 the species Lonchitis and aculeatum were identical, that Lonchitis 

 was the young or seedling form of the plant prevented by 

 situation from acquiring its normal or perfect form, and that 

 aculeatum was the same plant in its normal or perfect form. I 

 traced the plant beyond all dispute from the simply pinnate frond 

 represented at page 40, to the more compound fronds f and 0, 

 (page 39), and I not only found that the plant advanced from i 

 (page 40) to /(page 39), and from that again to e (page 39), but 

 I found that by reversing the treatment, it could be compelled to 

 retrograde, and reassume the simply pinnate form represented at 

 h (page 39). 



In the Botanic Garden at Belfast I have since seen a plant of 

 a totally different character : on this, long cultivation had pro- 

 duced no trace of a similar effect in fact, a contrary effect was 

 obvious, for it not merely bore the Lonchitis characters, but bore 

 them to an excess, and had departed further from any trace of 

 aculeatum character than any specimen of Lonchitis that I had 

 ever seen. I afterwards found the same plant in the College and 

 Glasnevin Botanic Gardens at Dublin, and in these also it 

 presented its peculiar characters with unvarying fidelity. I am 

 equally at a loss how to place this stubborn and unvarying plant 

 with aculeatum, the most Protean of all our species, and how to 

 give figures and assign characters to each, which shall clearly 

 distinguish it from the other. 



The roots of the present plant are long, strong, black, and 

 wiry ; the rhizoma is thick, tufted, and scaly ; the fronds appear 



