18 LICHENOGRAPHICAL NOTES. 
Ë 
the smaller number in the later one are arranged under 25 species. 1s, 
therefore, Mudd more simple and intelligible, and is Leighton a greater 
multiplier of distinctions? Is it more 
ia gracilis, var. hybrida, forma chordalis, than as O. gracilis, vat. 
chordalis? Or again, where is the great simplicity in naming the plant 
figured in Eng. Bot. 2051 (and called by Leighton Cladonia cornuco- 
pioides), C. coccifera, var. cornucopioides, forma pleurota 
A second consideration vitiates any such comparisons in the gross be- 
tween the floras of a limited tract of country, which is, that many plants 
which appear only in the later flora were not included in the former, not 
because they had not been distiuguished and named at the date of its pub- 
lication, but because, though found in other places, they had not been de- 
tected in the district to which the flora pertained 
If we wish to find the increase of “new species," truly to be calied 
such, with any degree of accuracy, we must adopt a different plan, and 
see when the plants enumerated as belonging to our flora were first dis- 
tinguished. 
Considered in this way, we find that of the 781 species enumerated in 
the ‘Lichen Flora, 540 had been named by premicroscopic authors, or at 
all events before 1351. An increase, therefore, is apparent of 241 species, 
or about 443 per cent., to be laid to the charge of modern splitters or ' 
species-makers. 
It may, however, be urged against this plan that many plants which 
take rank as species in Leighton’s work (as for instance, Cladonia pungens) 
were considered varieties by some previous authors. ut when we re- 
collect what book-species and book-varieties really are, and that the 
varieties of one author are the species of a second, or, if regarded as varie- 
ties, are assigned to quite a different type,—this objection loses very much 
of its force. C. pungens, for instance, was considered a distinct species by 
Acharius in his * Methodus, by Delise, Kórber, Floerke, in Eng. Bot., 
and by Hooker ; it was assigned to C. rangiferina by Acharius in the 
* Synopsis,’ and by Wahlenberg; and to Surcata by Acharius in his Lich. 
Univ., by Fries, Schzerer, and Nylander. 
And, besides number thus raised to specific rank is probably 
compensated in great measure by the number degraded to varietal stand- 
in 
g. 
In any case, however, in comparisous made for the purpose this is, it 
