DE CANDOLLE ON SPECIES. 
199 
beings, which have for a quarter of a century been familiar to the 
naturalists of this country, thanks especially to the writings of Lyell, 
Darwin, and E. Eorbes, are slowly making their way on the Conti¬ 
nent ; and it is no small gratification to find that they assume that 
importance in this essay of M. De Candolle, which it was thought they 
should have held in his learned “ Greographie Botanique;” and such 
being the case, we are not disposed to cavil at the impression which the 
essay too much conveys, that many of these considerations, and even 
the most trite of his conclusions, are original on its author’s part, and 
suggested for the first time to his mind by a study of the Cupuliferae. 
It remains, however, to give these conclusions, all important as 
some of them are, and familiar to English naturalists, in the words of 
their author. He says, “ To return to this work, in which secondary 
and minute observations have led me by degrees to the consideration 
of the most important scientific questions, I affirm— 
“ 1. It is not impossible, by means of numerous well selected 
specimens, to establish in Botany groups comprised one within 
another, of which the lowest series are very numerous, very badly 
limited, forming subvarieties, varieties and races, by means of charac¬ 
ters often varying in the same individual; the so-called varieties or 
races being grouped in species a little less vaguely limited, the species 
forming sufficiently precise genera, insomuch that all mankind have 
recognized these generic groups and given them substantive names 
(as oak, poplar, gentian, &c.). Lastly, those genera form groups 
which themselves are comprised in others.” (As before stated, we 
take exception to every term of this proposition, except the self- 
evident first,—that plants can be grouped, and the last, that genera 
may be grouped as well as species, &c.) 
“ 2. Many of the groups found in books are doubtful and provi¬ 
sional, especially those of the lower degrees, for they are founded 
on a few specimens, or on analogies and presumption, and not upon 
numerous specimens.” 
This is true as far as it goes, but not the whole truth ; nor are 
the causes altogether relevant; were they so, the Systema of Linnaeus 
would be one of the worst systematic works, instead of the best. 
“ 3. There is a tendency to hereditariness of forms and functions 
in all these groups, even the lowest, which affects the most trifling 
character, but it is never complete or uniform, and there are always 
differences either very slight, or slight, or considerable, which are 
either transitory or permanent, between one generation and the suc¬ 
ceeding. 
“ 4. Existing geographical distribution, combined with the study 
of fossil plants of the modern epoch, reveals frequent changes in the 
limits of varieties, races and species, according to successive physical 
or geographical circumstances, but unaccompanied with appreciable 
changes of form or of function. 
“ 5. Groing back to the tertiary epoch in Europe, we may assume 
that there have been changes of form over and above the changes of 
