THE ENTOMOLOGISTS 
WEEKLY INTELLIGENCER. 
No. 97.] SATURDAY, AUGUST 7, 1858. 
DEVELOPMENT- 
That man was originally a polyp, and 
assumed his present form and qualities 
through a graduated seale of fish, lizards 
and mammalia, is a statement so strong, 
and apparently so absurd, that the most 
elaborate argument in support of it will 
fail to bring conviction. But the truth 
or falsehood of this assertion must be 
fought out by the separation of closely 
allied species. 
It is very possible to conceive, that two 
species may exist so closely allied as to 
he inseparable in the present state of 
our knowledge, just as Acronycta Psi 
and Tridens never would or could have 
been separated if the larvae had remained 
unknown ; and on the other hand we 
may conceive another species living 
everywhere, feeding on everything, and 
varying with every change of circum- 
stance. We are not saying that any 
such species do exist, but that we can 
conceive them possible, and every one 
of our readers will he able to recall 
instances tending in one or other of 
these directions. 
Here then is the difficulty. What 
is a species? Is the barrenness of 
[Price \ d . 
hybrids an unfailing test of distinctness ? 
Is it a universal test ? Is it the only 
test? To what extent can a species 
be altered by circumstances ? Will a 
species which has by circumstances been 
altered from its original form, always 
return to that form, when the peculiar 
circumstances which modified it are 
removed ? 
These are some of the points which 
require elucidation ; hut the subject is 
very wide, including the whole animal 
and vegetable world; it is identical with 
the discussion now going on amongst 
ethnologists, and which is daily in- 
creasing in importance, and, from the 
rapidity of the succession of insect 
generations, entomologists are most 
favourably circumstanced for throwing 
light upon the subject. May not a 
few experiments, carefully performed, 
prove that all the Aphides on the sur- 
face of the globe are one species modified 
only by the food-plant and climate? 
We recommend this seriously to Mr. 
Francis Walker’s consideration. 
What we want is experiment and 
observation —patient, long-continued and 
accurate; and to those who have been 
accustomed to rear insects from gene- 
ration to generation, and are now 
u 
