and varieties, or he may give me trouble by arriving at another conclusion, but at all events his facts will be given for me to work upon.  Your collections and my own will furnish most valuable material to illustrate and prove the universal applicability of the hypothesis.  The connection between the succession of affinities and the geographical distribution of a group, worked out species by species, has never yet been shown as we shall be able to show it.  In this Archipelago there are two distinct faunas rigidly circumscribed, which differ as much as those of South America and Africa, and more than those of Europe and North America:  yet there is nothing on the map or on the face of the islands to mark their limits.  The boundary line often passes between islands closer than others in the same group.  I believe the western part to be a separated portion of continental Asia, the eastern the fragmentary prolongation of a former Pacific continent.  In mammalia and birds the distinction is marked by genera, families, and even orders confined to one region; in insects by a number of genera and little groups of peculiar species, the families of insects having generally a universal distribution.

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Ternate, January 25, 1858.

I have not done much here yet, having been much occupied in getting a house repaired and put in order.  This island is a volcano with a sloping spur on which the town is situated.  About ten miles to the east is the coast of the large Island of Gilolo, perhaps the most perfect entomological terra incognita now to be found.  I am not aware that a single insect has ever been collected there, and cannot find it given as the locality of any insects in my catalogues or descriptions.  In about a week I go for a month collecting there, and then return to prepare for a voyage to New Guinea.  I think I shall stay in this place two or three years, as it is the centre of a most interesting and almost unknown region.  Every house here was destroyed in 1840 by an earthquake during an eruption of the volcano....

What great political events have passed since we left England together!  And the most eventful for England, and perhaps the most glorious, is the present mutiny in India, which has proved British courage and pluck as much as did the famed battles of Balaclava and Inker-man.  I believe that both India and England will gain in the end by the fearful ordeal.  When do you mean returning for good?  If you go to the Andes you will, I think, be disappointed, at least in the number of species, especially of Coleoptera.  My experience here is that the low grounds are much the most productive, though the mountains generally produce a few striking and brilliant species....—­Yours sincerely,

ALFRED R. WALLACE.

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TO F. BATES