II 
note I luentioncil that the former species had tactually been found 
there. 
there is another species, A.qvoHs fnfia, which I did not men- 
tion because it occurs sparingly on inland heaths, but is only 
found in such situations of a dull l.rown colour, while on coast 
sandhills, where it swarms, it is generally distinctly and richly 
coloured and marked, and varies from whitish, avith dark markings, 
to almost a jet black. 
Having during the past season had further opportunities of 
investigating this subject, I venture to offer a few more facts bear- 
ing u])on it, especially with riderencoto the thi'ce species just named. 
In August last I had the jileasure of finding culUrjera in 
the greatest profusion at Ifrandon, freipienting the flowers of 
Scabiom (Knautia) arvensi\ both by day and night, and with it an 
abundance of Agrotis tn'tici, of prt^cisely the rich, deep style of 
colour and markings which characterize it on the coast, but although 
I worked long and hard, I was unable to find a single specimen of 
Agrotis cursoria. 
Now, as this last species is the most plentiful of the three on 
the present coast of Norfolk, the fact of its total absence from the 
Lreck sand, if, as I believe, this can bo sustained, must be a 
convincing proof that the other species are not likely to have 
reached their present situation by emigration across the inter- 
vening land, from the present coast. 
But the question naturally arises at once— Why should Agrotis 
cursoria bo absent? Although so excessively abundant at Yar- 
mouth, Caistor, Hunstanton, and probably on all the .sandliills of 
the Norfolk and Suffolk coast, it is by no means so plentiful on 
those of the south and west of England, and in Ireland, as far as 
my observations have gone, for from common. 
It .seems, therefore, not unreasonable to suppose that it may be 
an immigrant from the eastward, at a comparatively recent date, 
and that it has attained its greatest abundance on the spot where 
it tirst obtained a footing. It would not, therefore, have been an 
inhabitant ot this portion of the post-glacial sea-coast. On the 
other hand, most ot the species already mentioned as found there, 
are (piite as plentiful on the western coast as on our o^^^l, some of 
them more so— Agrotis vaHigera and tritici, and Mamestra alhi- 
coton, for instance. 
