test variety of form and colouring. South
America, North India, and the Malay Islands are the regions where these
fine insects occur in the greatest profusion, and where they actually
become a not unimportant feature in the scenery. In the Malay Islands in
particular, the giant Ornithopterae may be frequently seen about the
borders of the cultivated and forest districts, their large size,
stately flight, and gorgeous colouring rendering them even more
conspicuous than the generality of birds. In the shady suburbs of the
town of Malacca two large and handsome Papilios (Memnon and Nephelus)
are not uncommon, flapping with irregular flight along the roadways, or,
in the early morning, expanding their wings to the invigorating rays of
the sun. In Amboyna and other towns of the Moluccas, the magnificent
Deiphobus and Severus, and occasionally even the azure-winged Ulysses,
frequent similar situations, fluttering about the orange-trees and
flower-beds, or sometimes even straying into the narrow bazaars or
covered markets of the city. In Java the golden-dusted Arjuna may often
be seen at damp places on the roadside in the mountain districts, in
company with Sarpedon, Bathycles, and Agamemnon, and less frequently the
beautiful swallow-tailed Antiphates. In the more luxuriant parts of
these islands one can hardly take a morning's walk in the neighbourhood
of a town or village without seeing three or four species of Papilio,
and often twice that number. No less than 130 species of the family are
now known to inhabit the Archipelago, and of these ninety-six were
collected by myself. Thirty species are found in Borneo, being the
largest number in any one island, twenty-three species having been
obtained by myself in the vicinity of Sarawak; Java has twenty-eight
species; Celebes twenty-four, and the Peninsula of Malacca, twenty-six
species. Further east the numbers decrease; Batchian producing
seventeen, and New Guinea only fifteen, though this number is certainly
too small, owing to our present imperfect knowledge of that great
island.

_Definition of the word Species._

In estimating these numbers I have had the usual difficulty to
encounter, of determining what to consider species and what varieties.
The Malayan region, consisting of a large number of islands of generally
great antiquity, possesses, compared to its actual area, a great number
of distinct forms, often indeed distinguished by very slight
characters, but in mos