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The majority of the individuals, therefore, can never make full use of their enormously powerful wings, till the exceptional case occurs of an individual being blown out to sea, or driven to emigrate by the incursion of some carnivorous animal, or the pressure of scarcity of food. A modification exactly opposite to that which produced the wingless birds (the Apteryx, Cassowary, and Dodo), appears to have here taken place; and it is curious that in both cases an insular habitat should have been the moving cause. The explanation is probably the same as that applied by Mr. Darwin to the case of the Madeira beetles, many of which are wingless, while some of the winged ones have the wings better developed than the same species on the continent. It was advantageous to these insects either never to fly at all, and thus not run the risk of being blown out to sea, or to fly so well as to he able either to return to land, or to migrate safely to the continent. Pad flying was worse than not flying at all.

So, while in such islands as New Zealand and Mauritius far from all land, it vas safer for a ground-feeding bird not to fly at all, and the short-winged individuals continually surviving, prepared the way for a wingless group of birds; in a vast Archipelago thickly strewn with islands and islets it was advantageous to be able occasionally to migrate, arid thus the long and strong-winged varieties maintained their existence longest, and ultimately supplanted all others, and spread the race over the whole Archipelago.

Besides this pigeon, the only new bird I obtained during the trip was a rare goat-sucker (Batrachostomus crinifrons), the only species of the genus yet found in the Moluccas. Among my insects the best were the rare Pieris arum, of a rich chrome yellow colour, with a black border and remarkable white antenna--perhaps the very finest butterfly of the genus; and a large black wasp-like insect, with immense jaws like a stag-beetle, which has been named Megachile Pluto by Mr. B. Smith. I collected about a hundred species of beetles quite new to me, but mostly very minute, and also many rare and handsome ones which I had already found in Batchian. On the whole I was tolerably satisfied with my seventeen days' excursion, which was a very agreeable one, and enabled me to sea a good deal of the island. I had hired a roomy boat, and brought with me a small table and my rattan chair.

These were great comforts, as, wherever there was a roof, I could immediately instal myself, and work and eat at ease. When I could not find accommodation on shore I slept in the boat, which was always drawn up on the beach if we stayed for a few days at one spot.