28 
on this question that, having cleared my conscience by the above 
advice, I am not afraid to give you my ideas upon it. Surely if the 
position which I have taken is anywhere near the true one, the 
numerical aspect really does not enter into the question at all. Let 
me explain what I mean. Sometimes we read, or hear announced at 
a meeting, that this or that local or scarce species was unusually 
abundant at such-and-such a time and place, and that the writer or 
speaker “ had no difficulty in collecting a thousand specimens.” 
Immediately the unthinking among us hold up our hands in pious 
horror, and perhaps threaten to excommunicate the unfortunate 
“ exterminator.” We turn over the next page (or listen to the next 
speaker, as the case may be) and learn that so-and-so “ was very scarce 
this season ; it cost me almost incessant hard work during the time it 
was out to secure a dozen examples.” Probably we pass over the 
record without criticism, or we sympathise with the collector on his 
failure, or even congratulate him on his perseverance. But which 
of the two, think you, was the real “ over-collector,” assuming that it 
lay within the power of either to come under this stigma ? Surely if 
it be possible to do permanent mischief to a particular species at all, 
it is by persecuting it when it is at its weakest, not by taking large 
numbers when it is at its zenith. Surely the state of the case is as 
mathematically demonstrable as is that of “ Mullerian Mimicry,” which 
its ingenious expounder has worked out so statistically. 
Let us suppose the case of a moth with whose resting habits a cer¬ 
tain local collector is really well acquainted, so that he stands a good 
chance, if diligent enough, of finding a good percentage of the speci¬ 
mens which successfully complete their metamorphoses in his district. 
Let us suppose, further, that, on account of the action of other than 
human enemies, this species is liable to very great fluctuations in point 
of number. Our collector, we will say, is able to give sufficient time 
to hunting it to be able to secure, on an average, just 50 per cent, of 
the total occurring. Now, the year 1002, perhaps, was a very bad year 
for it, and only 20 specimens from this little colony reached maturity. 
Of these our entomologist takes ten, most or all of them freshly 
emerged — there are several species which are best found at rest at this 
period. Consequently he only leaves ten, some of which may fall a 
prey to bats, or meet with one or another of the untold casualties which 
befall the moth tribe. It is just possible that in the long run so few 
impregnated females will have escaped for oviposition that the colony- 
unless speedily reinforced by immigration — may entirely work itself 
out in a generation or two by a too close inbreeding. But the year 
1901 was as favourable for the species as 1902 was the reverse ; 2.000 
came to maturity, and again our friend got his usual percentage. This, 
and not any suspicion of “over-collecting,” explains his abnormal 
“ bag ” of i,000, but we must not lose sight of the fact that he has 
also left another thousand to “ be fruitful and multiply and replenish 
the earth.” If the foregoing be even approximately the true statis¬ 
tical basis of the question, it follows, logically, that our theory of over¬ 
collecting ought to be that it bears an exact ratio to the amount of 
hard work (of course assuming that it be also well-directed and suc¬ 
cessful work) applied to the quest by the entomologist. 
1 have called attention to this matter solely in order to defend some 
quite innocent members of our brotherhood from thoughtless — though 
