DE CANDOLLE ON SPECIE3. 
193 
is an old doctrine of M. De Candolle’s, and being here repeated by 
him after many years experience, we have felt it to be our duty to 
weigh its merits well afresh, and have arrived at the same result as 
heretofore—that it is true in so limited a sense that it is better 
abandoned altogether. It is true, as he reminds us, that the divisions 
between Cryptogams and Phsenogams, and between Monocotyledons 
and Dicotyledons are sharp and clear, but this amounts to no more 
than the establishment of three groups, under which the 100,000, or, 
according to some, the 250,000 # known plants, are grouped. In the 
smaller division, the Cryptogams, the 3 great groups, Perns and their 
allies, Musci and theirs, Hepatic* and theirs, are further trenchantly 
limited, and these again from the remainder, or Thallogens, but 
between the members of these latter, Pungi, Algae, and Lichenes, no 
limit exists, and assuredly the genera of each and all the groups of 
Cryptogams are incomparably more unstable than the species, variable 
as they are. In the Phaenogams matters are still worse, the natural 
orders of Monocotyledons have never yet been grouped into well 
limited subclasses, nor have the orders been well limited themselves ; 
most assuredly the species of Qraminece , Orchidece , Liliacece , Iridece , 
and Amaryllidece , are incomparably better limited than the genera of 
those orders, and these again than the tribes. Lastly, turning to the 
class of Dicotyledons, the classification of their natural families into 
subclasses is the reproach of systematic botany in the eyes of those 
who believe that these can be so grouped, and the despair of all 
who (with sufficient knowledge and experience) have tried to group 
them. As it is, there are no less than 5 methods in vogue in works 
of standard authority now publishing, followed respectively as De 
Candolle’s and Lindley’s in England, Brongniart’s in Prance, End- 
licher’s in Germany, and Pries’ in Scandinavia, besides others in less 
vogue all over the continent. Descending in the scale, we find such 
diversity of amount of limitability of the higher and lower groups 
between Species and Orders, that no general conclusions can yet be 
drawn; there is the great Order Leguminosce, and its three sub-orders, 
all trenchantly limited, whose genera and species are, on the whole, 
all well limited and natural also, but which cannot be collected into 
tribes ; in Ranunculacece the tribes and genera are well limited, but a 
large proportion of the species are most variable; in Myrtacece , the 
species are much better limited than the genera ; in Composites the 
two suborders are well limited; but the tribes, subtribes, genera, and 
species, very badly ; and, finally, in UmbellifercE and Cruciferce , two of 
the best limited Orders, the tribes, genera, and species are all unstable 
and indeterminable alike. Lastly, we may cite the experience of the 
authors of the “ Genera Plantarum ” for the fact, that of the 55 Orders 
contained in the first part of that work, the limits of fully three-fourths 
* M. De Candolle’s estimate of Phsenogamic plants in the “ Geographic Botanique/’ 
but probably not that he now entertains. 
N. H. R.-—1863. 
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