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Arrangement and Geographical Distribution of the

Malayan Papilionidæ. Arrangement.--Although the species of Papilionidæ inhabiting the Malayan region are very numerous, they all belong to three out of the nine genera into which the family is divided. One of the remaining genera (Eurycus) is restricted to Australia, and another (Teinopalpus) to the Himalayan Mountains, while no less than four (Parnassius, Doritis, Thais, and Sericinus) are confined to Southern Europe and to the mountain-ranges of the Palæarctic region.

The genera Ornithoptera and Leptocircus are highly characteristic of Malayan entomology, but are uniform in character and of small extent. The genus Papilio, on the other hand, presents a great variety of forms, and is so richly represented in the Malay Islands, that more than one-fourth of all the known species are found there. It becomes necessary, therefore, to divide this genus into natural groups before we can successfully study its geographical distribution.

Owing principally to Dr. Horsfield's observations in Java, we are acquainted with a considerable number of the larvæ of Papilios ; and these furnish good characters for the primary division of the genus into natural groups. The manner in which the hinder wings are plaited or folded back at the abdominal margin, the size of the anal valves, the structure of the antennæ, and the form of the wings are also of much service, as well as the character of the flight and the style of

colouration. Using these characters, I divide the
Malayan Papilios into four sections, and seventeen
groups, as follows:
Genus ORNITHOPTERA.

a. Priamus-group.
C. Brookeanus-group.s

Black and green.
b. Pompeus-group. Black and yellow.
Genus PAPILIO,
A. Larvæ short, thick, with numerous fleshy tubercles ;

of a purplish colour. a. Nox-group. Abdominal fold in male very large;

anal valves small, but swollen ; antenna moderate; wings entire, or tailed; includes the Indian

Philoxenus-group. b. Coon-group. Abdominal fold in male small; anal

valves small, but swollen; antennæ moderate;

wings tailed. c. Polydorus-group. Abdominal fold in male small,

or none; anal valves small or obsolete, hairy;

wings tailed or entire. B. Larve with third segment swollen, transversely or

obliquely banded; pupa much bent. Imago with abdominal margin in male plaited, but not reflexed; body weak; antennæ long; wings much

dilated, often tailed. d. Ulysses-group.

| Protenor - group (Indian) is e. Peranthus-group. somewhat intermediate bef. Memnon-group. tween these, and is nearest

I to the Nox-group.
g. Helenus-group.
h. Erectheus-group.
i. Pammon-group.

k. Demolion-group. C. Larvæ subcylindrical, variously coloured. Imago with

abdominal margin in male plaited, but not reflexed; body weak; antennæ short, with a thick curved club; wings entire.

1. Erithonius-group. Sexes alike, larva and pupa

something like those of P. Demolion. m. Paradoxa-group. Sexes different. 11. Dissimilis - group. Sexes alike; larva bright

coloured; pupa straight, cylindric. D. Larvæ elongate, attenuate behind, and often bifid, with

lateral and oblique pale stripes, green. Imago with the abdominal margin in male reflexed, woolly or hairy within; anal valves small, hairy;

antennæ short, stout; body stout. 0. Macareus-group. Hind wings entire. p. Antiphates-group. Hind wings much tailed (swal

low-tails).

q. Eurypylus-group. Hind wings elongate or tailed. Genus LEPTOCIRCUS.

Making, in all, twenty distinct groups of Malayan Papilionidæ.

The first section of the genus Papilio (A) comprises insects which, though differing considerably in structure, having much general resemblance. They all have a weak, low flight, frequent the most luxuriant forestdistricts, seem to love the shade, and are the objects of mimicry by other Papilios.

Section B consists of weak-bodied, large-winged insects, with an irregular wavering flight, and which, when resting on foliage, often expand the wings, which the species of the other sections rarely or never do. They are the most conspicuous and striking of eastern Butterflies.

Section C consists of much weaker and slower-flying insects, often resembling in their flight, as well as in their colours, species of Danaidæ.

where they gather opeedily suckinund in the

Section D contains the strongest-bodied and most swift-flying of the genus. They love sunlight, and frequent the borders of streams and the edges of puddles, where they gather together in swarms consisting of several species, greedily sucking up the moisture, and, when disturbed, circling round in the air, or flying high and with great strength and rapidity.

Geographical Distribution.—One hundred and thirty species of Malayan Papilionidæ are now known within the district extending from the Malay peninsula, on the north-west, to Woodlark Island, near New Guinea, on the south-east.

The exceeding richness of the Malayan region in these fine insects is seen by comparing the number of species found in the different tropical regions of the earth. From all Africa only 33 species of Papilio are known; but as several are still undescribed in collections, we may raise their number to about 40. In all tropical Asia there are at present described only 65 species, and I have seen in collections but two or three which have not yet been named. In South America, south of Panama, there are 150 species, or about oneseventh more than are yet known from the Malayan region; but the area of the two countries is very different; for while South America (even excluding Patagonia) contains 5,000,000 square miles, a line encircling the whole of the Malayan islands would only include an area of 2,700,000 square miles, of which the land-area would be about 1,000,000 square miles. This superior

richness is partly real and partly apparent. The breaking up of a district into small isolated portions, as in an archipelago, seems highly favourable to the segregation and perpetuation of local peculiarities in certain groups ; so that a species which on a continent might have a wide range, and whose local forms, if any, would be so connected together that it would be impossible to separate them, may become by isolation reduced to a number of such clearly defined and constant forms that we are obliged to count them as species. From this point of view, therefore, the greater proportionate number of Malayan species may be considered as apparent only. Its true superiority is shown, on the other hand, by the possession of three genera and twenty groups of Papilionidæ against a single genus and eight groups in South America, and also by the much greater average size of the Malayan species. In most other families, however, the reverse is the case, the South American Nymphalidæ, Satyridæ, and Erycinidæ far surpassing those of the East in number, variety, and beauty.

The following list, exhibiting the range and distribution of each group, will enable us to study more easily their internal and external relations.

Range of the Groups of Malayan Papilionida. Ornithoptera. 1. Priamus - group. Moluccas to Woodlark

Island ... ... ... ... ... ... 5 species. 2. Pompeus - group. Himalayas to New

Guinea, (Celebes, maximum) ... ... 11
3. Brookeana-group. Sumatra and Borneo... 1 »

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