34 
following year it had shifted again to a third locality, and now for 
the last two years it has either disappeared altogether, or chosen a 
locality which I have not been able to discover. Other species 
again show just the reverse tendency, instead of being confined to 
one spot, they turn up singly under very different circumstances, 
and in very different places. Moreover the widely distributed 
species are not such as we should expect. I have been much struck 
in comparing Indian with European Lepidoptera, to find, that 
with the exception of the painted lady (Cynthia cardui) which seems 
to he a cosmopolite, and Danais chrysippus, there is scarcely one 
amongst the active and quick flying Rhopalocerse that is common to 
the two continents. On the other hand amongst the Sphingidse, 
many of which are very sluggish insects, I find two species of 
Acherontia, (Death’s Head Moth) scarcely to be distinguished from 
the European one, while the Indian specimens of Sphinx convolvuli, 
Chterocampa nerii, Chserocampa celerio, and Macroglossa stella- 
tarum seem to be identical with the European ones. I think that 
by a careful study of the distribution of insects over a limited area, 
we shall be more likely to understand facts like these than in any 
other way, for in all natural phenomena the laws which regulate 
those of minor consequence and of more limited prevalence, govern 
those also which have a greater importance and a more extended 
influence. 
Practically speaking, I think that the Lepidoptera of Norfolk 
at least may be divided, according to the localities they frequent, 
into five groups : — 
1st. The marsh species. These, of course, are more particularly 
to be sought for amongst the broads of East Norfolk, and deserve 
particular attention^ as there are many amongst them whose life 
histories are not as yet known, and which are scarcely to be found 
elsewhere in England. 
2nd. The heath-loving species. These are also well repre- 
sented in Norfolk, and amongst them is a small group of species, 
including Lithostege nivearia, Acidalia rubricata, and Agrophila 
sulphuralis, which seem to be limited to a narrow strip of country 
on the borders of Norfolk and Suffolk, in the neighbourhood of 
Thetford and Brandon. These insects, and the cause of their 
narrow limits, require investigation. 
3rd. The coast insects. These are found chiefly on the flat. 
