as
a very short tail; while far east, in New Guinea and the adjacent
islands, the tail has almost entirely disappeared.

In the Polydorus-group two species, P. Antiphus and P. Diphilus,
inhabiting India and the Indian region, are tailed, while the two which
take their place in the Moluccas, New Guinea, and Australia, P.
Polydorus and P. Leodamas, are destitute of tail, the species furthest
east having lost this ornament the most completely.

Western species, Tailed. Allied Eastern species not Tailed.

Papilio Pammon (India) P. Thesus (Islands) minute tail.
P. Agamemnon, var. (India) P. Agamemnon, var. (Islands).
P. Antiphus (India, Java) P. Polydorus (Moluccas).
P. Diphilus (India, Java) P. Leodamas (New Guinea).

The most conspicuous instance of local modification of form, however, is
exhibited in the island of Celebes, which in this respect, as in some
others, stands alone and isolated in the whole archipelago. Almost every
species of Papilio inhabiting Celebes has the wings of a peculiar shape,
which distinguishes them at a glance from the allied species of every
other island. This peculiarity consists, first, in the upper wings being
generally more elongate and falcate; and secondly, in the costa or
anterior margin being much more curved, and in most instances exhibiting
near the base an abrupt bend or elbow, which in some species is very
conspicuous. This peculiarity is visible, not only when the Celebesian
species are compared with their small-sized allies of Java and Borneo,
but also, and in an almost equal degree, when the large forms of Amboyna
and the Moluccas are the objects of comparison, showing that this is
quite a distinct phenomenon from the difference of size which has just
been pointed out.

In the following Table I have arranged the chief Papilios of Celebes in
the order in which they exhibit this characteristic form most
prominently.

Papilios of Celebes, having the Closely allied Papilios of the
wings falcate or with abruptly surrounding islands, with less
curved costa. wings and slightly falcate curved costa.

1. P. Gigon P. Demolion (Java).
2. P. Pamphylus P. Jason (Sumatra).
3. P. Milon P. Sarpedon (Moluccas, Java).
4. P. Agamemnon, var. P. Agamemnon, var. (Borneo).
5. P. Adamantius P. Peranthus (Java).
6. P. Ascalaphus P