On the present state of Zoology. % \ 
principles : It is undoubtedly allowable, without waiting- for the ac- 
quirement of all possible facts that can be obtained, to try any theory 
which explains those already in our possession, by applying it to 
such as may be observed afterwards. But the danger is, in the science 
now before us, especially when we have to deal with analogical rela- 
tions, that we mistake for facts points, which may certainly appear 
as such to us, but which are of that nature that they must infallibly 
strike different observers in different lights according to the impres- 
sions upon the mind at the time of viewing them. Hence it is that 
we conceive, that we are more likely to see these relations truly, when 
we have no theory to support ; when there is nothing which is like- 
ly to warp our judgment. We believe that if we made it our first en- 
deavour to arrange all animals according to their best ascertained af- 
finities, at the same time noting any other less obvious relation ; and 
if we then drew lines of separation between such groups as appeared 
well characterized, taking care to assign to each a rank proportioned 
to its true value ; we should gradually arrive in this manner at as 
just a conception of the true order of nature as, perhaps, it is possible 
to attain. * For, after all, it becomes a question, whether, assuming 
that there is some definite plan in nature grounded upon fixed prin- 
ciples, we can ever hope to understand more than part of it. When 
we consider how much is requisite to complete the history of a single 
species, and that we need to be acquainted with this history, not only 
in the case of all existing animals, but of all lost ones also, we may 
conceive how vast must be the task of tracing the relations which one 
species bears to the others. We can scarcely do more than make some 
approximation to the truth. We can only arrange our groups in such 
a manner, that there be no other known ones more nearly allied to 
be brought in between those which stand next each other. And the 
system which does this may be called natural, f although it may not 
* The above will be found nearly in accordance with Lamarck's judicious ob- 
serration on this subject,, which it may be well to repeat here. He says, 
" Nous avons senti que, pour reussir a etablir une bonne distribution des animaux, 
sans que 1'arbitraire de 1'opinion en affaiblisse nulle part la solidite, il etait ne- 
cessaire, avant tout, de rapprocher les animaux les uns des autres, d'apres leurs 
rapports les mieux determines ; et qu' ensuite, Ton pourrait, sans inconvenient, 
tracer les lignes de separation qui detachent les masses classiques, ainsi que les 
coupes subordonnees, utiles a etablir, pourvu que les rapports ne fussent nulle 
part compromis par la composition et 1'ordre de nos diverses coupes." Hist. 
Nat. des An. sans Vert. (2d edit.) tome i. p. 285. 
f This remark is Cuvier's but we are unable to refer to the exact place in 
which it is expressed. 
