110 THE ENTOMOLOGIST’S WEEKLY INTELLIGENCER. 
which is essential to it, nor force into it 
any one which is not so, we must first 
acknowledge that it is one of the cha- 
racters of species to belong to a given 
period in the history of our globe, and to 
bold definite relations to the physical 
conditions then prevailing, and to animals 
and plants then existing. These rela- 
tions are manifold and are exhibited — 
1st, in the geographical range natural to 
any species, as well in its capability of 
being acclimatized in countries where it 
is not primitively found ; 2nd, in the 
connection in which they stand to the 
elements around them, when they in- 
habit either the water or the land, deep 
seas, brooks, rivers and lakes, shoals, flat, 
saudy, muddy or rocky coasts, limestone 
banks, coral reefs, swamps, meadows, 
Jiehls, dry lauds, salt deserts, sandy 
deserts, moist land, forests, shady groves, 
sunny hills, low regions, plains, prairies, 
high table-lauds, mountain peaks, or the 
frozen barrens of the Arctics, &c. ; 3rd, in 
their dependence upon this or that kind 
of food for their sustenance ; 4th, in the 
duration of their life; 5th, in the mode 
of their association with one another, 
whether living in flocks, small companies 
or isolated ; 6ih, in their period of repro- 
duction ; 7th, in the changes they undergo 
during their growth,^and the periodicity 
of these changes in their metamorphosis ; 
8th, in their association with other beings, 
which is more or less close, as it may 
only lead to a constant association in 
some, whilst in others it amounts to 
parasitism; 9ih, specific characteristics 
are further exhibited in the size to which 
animals attain, in the proportions of their 
parts to one another, in their ornamenta- 
tion, &c., and all the variations to which 
they are liable. 
As soon as all the facts bearing upon 
these diflferent points have been fully 
ascertained there can remain no doubt 
respecting the natural limitation of spe- 
cies ; and it is only the insatiable desire 
of describing new species from insuflicient 
data which has led to the introduction in 
our systems of so many doubtful species, 
which add nothing to our real know- 
ledge and only go to swell the nomen- 
clature of animals and plants, already so 
intricate. 
Assuming, then, that species cannot 
always be identified at first sight, and 
that it may require a long time and 
patient investigation to ascertain their 
natural limits; assuming further, that 
the features alluded to above are among 
the most prominent characteristics of 
species, we may say that species are 
based upon well-determined relations of 
individuals to the world around them 
and to their kindred, and upon the pro- 
portions and relations of their parts to 
one another, as well as upon their orna- 
mentation. Well-digested descriptions 
of species ought, therefore, to be com- 
parative; they ought to assume the cha- 
racter of biographies, and attempt to 
trace the origin, and follow the develop- 
ment, of a sjiccies during its whole 
existence. Moreover, all the changes 
which species may undergo in the course 
of time, especially under the fostering 
cure of man, in the state of domcsiicily 
and cultivation, belong to the history of 
the sjtecies ; even the anomalies and 
diseases to which they are subject belong 
