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 wings falcate or with abruptly curved costa. | Closely allied Papilios of the surrounding islands, with less falcate wings and slightly 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. Deiphontes (Gilolo). |
| 7. P. Sataspes | P. Helenus (Java). |
| 8. P. Blumei | P. Brama (Sumatra). |
| 9. P. Androcles | P. Antiphates (Borneo). |
| 10. P. Rhesus | P. Aristæus (Moluccas). |
| 11. P. Theseus, var. (male) | P. Thesus (male) (Java). |
| 12. P. Codrus, var. | P. Codrus (Moluccas). |
| 13. P. Encelades | P. Leucothoë (Malacca). |
It thus appears that every species of Papilio exhibits this peculiar form in a greater or less degree, except one, P. Polyphontes, allied to P. Diphilus of India and P. Polydorus of the Moluccas. This fact I shall recur to again, as I think it helps us to understand something of the causes that may have brought about the phenomenon we are considering. Neither do the genera Ornithoptera and Leptocircus exhibit any traces of this peculiar form. In several other families of Butterflies this characteristic form reappears in a few species. In the Pieridæ the following species, all peculiar to Celebes, exhibit it distinctly:—