(a bad 8) 
of the earth’s surface which have been established for other 
classes are applicable to insects. I think that the pro- 
portion of known as compared with unknown insects is still 
too small, and the classification of the known species still too 
uncertain, to allow the same methods to be applied to them 
that have been used for mammals by Wallace, for birds 
by Sclater and Sharpe, and for plants by Hooker, Dyer, and 
Hemsley; but still I think we might do more than we have 
done in this branch of our subject. 
Personally, I believe that it is still too soon to investi- 
gate, with much hope of success, the reasons for a thousand 
curious and apparently inexplicable facts which turn up in 
the study of distribution, and of which, I think, the speci- 
mens I am showing to-night, in illustration of these remarks, 
afford abundant proof; but I hope to draw the attention of 
our Fellows, and entomologists generally, to the backward 
position we occupy in this branch of zoological study. 
No one man has, or could have, sufficient knowledge of all 
orders to work out a scheme of geographical distribution for 
insects generally ; but we might individually do a good deal to 
throw light on the subject, in order to see how far the facts, 
as far as we are able to judge, agree with those derived from 
the study of plants, mammals, and birds. 
T hope eventually to review the subject more completely ; but 
in writing of the regions where I have personally travelled and 
collected, and of whose butterflies I have a fair knowledge, 
namely, Europe, Asia, and North America, I find so many 
doubtful and difficult questions, that I thought it best not to 
attempt more than a slight sketch of the affinities of regions 
like South America, Africa, and Australia, whose butterflies 
I know but very slightly, from the writings and observations 
of others; and shall, therefore, touch but very lightly upon 
them at present. 
In attempting to compare the distribution of insects with 
that of birds, animals, or plants, we are met by two great 
difficulties, which must make any exact definition of the 
regions and sub-regions impossible at present. One is the 
want of knowledge as to the insect fauna of many of the most 
important areas of which the animals, birds, and plants are 
