4 ANP IBIS ID ISG | NO)es its 
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OccurRENCE OF Paprr1io Macwaon IN DERBYSHIRE. 
(‘ Zoologist,’ ii. (1845) pp. 944 & 945.) 
As I find the capture of two specimens of the Swallow-tail Butterfly 
(Papilio Machaon) at Matlock, in Derbyshire, recorded in a former 
number of ‘ The Zoologist’ (Zool. 400), I feel myself bound to explain 
how this must have happened ; the passage was pointed out to me 
only a few days ago, or I should certainly have sent this explanation 
sooner. In the springs of 1843 and 1844, I procured a very large 
number (many hundreds) of the chrysalids of P. Machaon from 
Burwell Fen, and as the butterflies came out, by far the greater 
number of them were permitted to escape, partly for the pleasure of 
seeing them in the state of liberty, and partly in the hope that they 
might breed and continue to flourish in the neighbourhood ; at the 
same time, by so doing, they would disprove the common notion that 
local insects cannot be permanently transplanted. Most of those so 
turned out were at Matlock, but many were also liberated at Beeston, 
in Nottinghamshire, and some few dozens at Eton, in’ Buckingham- 
shire. I had the best prospect of success at Matlock, as there is not 
much mowing grass, whilst various umbelliferous plants abound on 
the rough grounds, and althongh the features of the country are the 
extreme opposite to those of Cambridgeshire, I was not without hopes, 
for I had heard that on the continent P. Machaon is found on hills: 
however, although some of the caterpillars were found in the 
neighbouring gardens, there does not seem much probability of 
ultimate success, for, even in Cambridgeshire, they are confined to 
the fens, and abound only where there is sedge. I am inclined to think 
that Sparrows and other birds would alone effectually stop their 
increase. I am aware that many naturalists will be much annoyed 
at my proceedings, and | am not at all prepared to defend myself, 
but in this case I in some degree avert the mischief by public avowal. 
If the practice of introducing insects, or plants (for my observations 
apply to them with even more force), were to become general, lists of 
local faunas would soon be of doubtful authority, and the highly 
interesting subject of the geographical range of sects and plants 
would be involved in error; still worse would be the loss of interest 
in our individual captures, which would be another certain result, and 
it would perhaps be as baneful to the health of the entomological 
world as the practice of buying specimens for our cabinets has already 
proved to be. For, even if dealers were universally honest, and none 
of them practised gross and mischievous deceptions, numbers of people 
must have been disgusted with Entomology, on seeing that the 
comparative excellence of their cabinets must depend so immediately 
on the length of their purses, rather than on their own industry and 
ingenuity : a rich man has an undue advantage, if advantage it be, 
but it seems much the same as if a squire were to buy the trophies of 
