66 
FERNS : BEITISH AND FOREIGN. 
wards be placed. But as many species of Linnaeus, 
Swartz, and other old, as well as modern authors, 
are but indifferently described, many being derived 
from imperfect specimens, and with nothing but the 
meagre description left us for their identification, it 
frequently happens that some modern author detects, 
or supposes he has found out, that the new species of 
his contemporary is one of the Linnaean or Swartzian 
doubtful species, and faith in his decision being 
admitted, familiar names become changed, thus bur- 
dening the science with additional synonyms, and 
rendering it in many cases impossible to reconcile one 
author’s views with another. As an instance of the 
different views of authors on the identification of 
species and their synonyms, the genus Asplenium is a 
good example, it having within these few years, and 
near about the same time, been revised by Dr. Mettenius, 
Sir W. J. Hooker, and Mr. Moore. The two latter 
had the advantage of profiting by Dr. Mettenius’s 
views, but in a great many cases I find it quite impos- 
sible to reconcile or agree with the views of either. 
As an example of the different views, I will cite the 
plant known in gardens for the last forty years by the 
name of Asplenium Sliepherdii. The above-mentioned 
authors place it as a synonym, each under a different- 
species and with different synonyms. To show the 
impossibility of reconciling one with the other, it will 
be sufficient to notice that in the Index Filicum it is 
found as one of twenty-three synonyms under Dipia- 
zium radicans. Believing as I do that these synonyms 
represent several distinct species, and the plant in 
question being one of them, I deem it best to retain 
it under the name it has been so long known by, and 
