FILICES. 105 



is still to be seen on some walls in that village ; but doubtless it has 

 originally been an escape from cultivation. 



Yar. fi. In a cavern south from the harbour of Cove, Kincardine- 

 shire, but now almost or quite extinct ; originally found there by the 

 late Professor Knight of Aberdeen, and distributed in a living state by 

 Dr. Dickie. The late Mr. C. Barter states he found it on rocks about 

 two miles beyond the Cove towards Lighthouse Point, where a small 

 rill falls over the rocks (Phyt. series ii. 1855-56, p. 509): I do not 

 know if this statement has been authenticated by competent authority. 

 Dr. Dickie writes that he " saw it on dripping walls and rocks near 

 the road about 3 or 4 miles north from Dunkeld, Perthshire." Very 

 probably some of the stations given for C. eu-fragilis, var. dentata, 

 belong to C. alpina, var. Dickieana. 



England, Scotland. Perennial. Summer, Autumn. 



Plant very similar to C. eu-fragilis, and about the same size. 

 Fronds 3 inches to 1 foot long, or a little more. Yar. a has the lamina 

 commonly much more divided, and the primary pinna? commonly 

 shorter and more ovate in outline, and usually more abruptly 

 pointed than in C. eu-fragilis : the narrow ultimate segments give the 

 pinnae some resemblance to those of Chcerophyllum Anthiscus. 



Yar. j3 bears a very close resemblance to C. eu-fragilis, var. dentata. In 



the wild plant of which I have seen but a single frond, both the pinna? 



and the pinnules are crowded; the pinna? slightly twisted and. the 



basal pinnules decurrent, and those towards the extremity of the pinna? 



confluent, so that the pinna? are pinnatipartite at the base and simply 



pinnatifid towards the apex. When cultivated, however, seedlings 



present not only this form of frond, but others which are much more 



deeply divided, so that the pinnae become bipinnate at the base and 



pinnatipartite towards the apex, and cease to be contiguous. The spores 



are precisely similar to those of C. alpina, having blunt rounded slightly 



elevated tubercles, and not long spine-like ones such as we find on the 



spores of C. eu-fragilis. This peculiarity of the spores Mr. Moore 



believes to have been first pointed out by Mr. Wollaston, and it is I 



think conclusive that Dr. Milde is right in referring the form 



Dickieana to C. alpina and not to C. eu-fragilis. As far as my 



experience goes, the sculpture of the spores is one of the most constant 



characters to be found among ferns ; and after cultivating C. Dickieana 



for many years, I have come to the conclusion that the tuberculatum 



of the spores remains constantly identical with that of C. alpina, and 



distinct from all the forms of C. eu-fragilis. In the more finely 



divided seedling plants there is a decided approach to the less divided 



forms of C. alpina, var. a, and the general outline of the frond is more 



like that of alpina than of C. eu-fragilis var. dentata, which resembles 



VOL. XII. P 



