4] 
3. Mackay. 
I found in 1805, on the limestone rocks at Mucruss, a beautiful 
and delicate variety of Adiantum-nigrum with fronds tripinnate 
throughout, or with pinnules deeply and finely laciniated. It was 
subsequently found by Miss Hutchins and Dr. Taylor, and Mr. W. 
Andrews lately gave me a specimen collected by him in 1835, on a 
mountain called Cahir Conree, six miles from Tralee.—Flora Hiber- 
nica, p. 342. 
4, FRANCIS. 
Sir J. E. Smith, in conformity with the old authors, makes another 
variety, differing only from the common plant in having long fronds 
and distant pinne ; but I leave any one to say if it be anything more 
than a drawn-up plant of the common species, found, as it was, solitary 
in a dark cave.—Analysis, p. 50, date 1842. 
5. Dr. ALLMANN. 
There may be some doubt as to the necessity of considering it 
separately from the common form of Adiantum-nigrum, for though the 
extreme forms are so remarkably distinct as to strike the most casual 
observer, yet these extremes are connected by such numerous grada- 
tions, by which they run into each other, that I believe it to be impos- 
sible to say where the common variety terminates and the rarer one 
commences: the great elegance, however, of well-marked specimens 
of the rarer variety, and the facility with which they may be distin- 
guished from the common form, seems to render a separate notice of 
the fern desirable British Ferns, p. 260. 
6. NEWMAN. 
Asplenium Adiantum-nigrum, var. acutum.—British Ferns, p. 259, 
date 1844. 
7. Hooker & ARNOTT. 
A variety of Asp. Adiantum-nigrum with linear pinnules is found 
by Mr. Wilson in Ireland, at Muckruss by Mr. Mackay.—Brit. Flora, 
p- 974. 
8. Moore. 
Asplenium Adiantum-nigrum y. acutum ; fronds tripinnate through- 
out; ultimate pinnules cut into linear sharply toothed segments. 
Asplenium Adiantum-nigrum var. acutum, Newm. 259. Asplenium 
acutum, Bory.—Asplenium Virgilii, Bory.—Tarachia acuta, Pres]. * * 
VOL. IV. G 
