(Vv) 
greater the number and diversity of the points of view embraced by the 
systematist, the greater the art required. The arrangement of Nylander 
reckons all organs as of equal value in the system; which should thus, in 
his hands, exhibit the same universality in form, as it certainly does in 
aim, and in its unequalled wealth of illustration. We find it notwith- 
standing at once becoming eclectical; as now one, and now another 
organ is assumed as determinative: and whatever the advantage of this 
disposition, as the means of communication of the most learned of lich- 
enologists, it is evident that it differs from other arrangements, not so 
much in the exclusion of selection (that is of the ‘artificial and arbi- 
trary’) as in the use made of it. 
The writer has aimed then, in the following pages, first, to simplify, 
and render more easily apprebensible, the larger divisions. And follow- 
ing still further the guiding thought of the great master of cryptogamic 
botany who has either defined or suggested the most of what has so far 
been reached, he has next attempted to simplify and reduce the genera; 
though here, a consideration of the spore-values has led, to a certain 
extent, in an opposite direction; whereby certain over-large groups are 
disposed in smaller ones. Massalongo! exhibits the extreme point reached 
in the externalization of the Lichen-idea by the analytical studies of the 
last thirty years; and he asserts or assumes the existence of at least 240 
genera within the limits of study of the present volume. Noteworthy 
indications of a reaction from this extreme, within what may perhaps be 
called the same school, are afforded by the classifications of Th. Fries,’ 
and Stizenberger,’ neither of whom recognizes, it should appear, quite 
half of these genera of Massalongo; as by that of J. Miller. And the 
contrast becomes marked, and the return towards Acharius and Fries 
distinct in Nylander, with whom only about a quarter of the genera 
referred to, of the Italian author, find acceptance: a proportion which is 
much the same with that afforded by the present treatise. It is in the 
same direction that we still look for the full reconciliation of the later 
knowledge, rich as it is in the accumulations of the past generation, with 
all that continues to hold its own of the earlier; and for a new and better 
1 Krempelhuber, Conspectus Syst. Lich. Massal. (Gesch. d. Lich. 2, p. 221). 
2 Genera Heterolichenum recognita. 1861. 
3 Beitrag cur Flechtensystematik. 1862. 
3 Principes de Classification des Lichens, ct Enumeration des Lichens des 
environs de Genéve. 1862. 
