150 THE ENTOMOLOGIST. 
does not occur annually therein. It is certainly possible that the 
species may breed regularly in almost any locality in which it has 
been observed, but that it rarely comes under the notice of the 
naturalist. I cannot, however, think this is probable, and should 
meet any such argument by reference to the remarks appended 
to notices of captures recorded by entomologists who have long 
resided in particular districts. From such observations it is quite 
clear that atropos is either a decided rarity in, or novel to, many 
localities in Great Britain. I submit that it is quite in accord 
with the facts to conclude that atropos is rather a wanderer in, 
than a denizen of, the greater portion of Britain, and that the 
imagines and larvee which occur outside those counties in which 
the species is more or less constant, are either migrants or the 
offspring of migrants. If it is admitted that atropos is a nomad, 
we may, without doing violence to the possible, very well suppose 
that examples sometimes, perhaps not infrequently or in small 
numbers, come to these islands from the continent. I cannot 
understand the abnormal abundance of the species in certain 
years in any other way than by supposing that our atropos are, 
at such times, assisted in the work of reproduction and 
distribution by immigrants. 
It is generally understood that there is but one brood of 
atropos each year in this country. Whether this is ordinarily 
the case or not I am unable to say, but in some years there would 
certainly appear to be two broods of the species with us. For 
instance, the nearly full-fed larve found at the end of June 
would surely attain the imago state before September. Probably 
such early larve are from ova deposited early in May,* and 
produce imagines at the end of July or beginning of August, and 
these again become the progenitors of the late September and 
October specimens as well as of those which remain in pupa 
until the following year. Then as to the parents of the June 
larve, the question which suggests itself to me is, Were they 
British born ?—that is, had they emerged from pup in any part 
of the British Islands? We see that, excepting the November 
specimen, Mr. Anderson did not get out his imagines before 
* In 1878 single specimens of atropos were taken on the South Devon 
coast, and on the sea-shore, Antrim, N. Ireland, on the 6th and 8th of May 
respectively, and another example was captured in the City of London, 
May 2nd, 1882.—R. 8. 
