Like a good UN spouse I followed my wife to Dhaka, not the most logical place in which to finalize a 2,000 page monograph on the 1,500 butterfly species of West Africa. But e-mail and digital photography have now made such a proposition much more realistic than it would have been ten years ago. And I have the vicariant pleasure of being almost certain that I am the only resident of Gulshan with more than 100,000 African butterflies in my study!

Even serious students of butterflies still do like to see real, live butterflies and not just those in boxes and on the computer screen. So I regularly take some time off to look at the wild butterflies in and around Dhaka. In principle the Dhaka area is not a promising one for butterflies, but despite pollution and the near absence of any natural vegetation, there are at least 70, probably 100, different species - which is about twice as many as in my own country, Denmark. And some of them are as large and beautiful as anywhere in the world.

My absolute favourite is the Common Jezebel (Delias eucharis) (fig. 1) with its wonderful bold combination of white, black, yellow, and crimson. There are three somewhat similar, but much rarer species. Their caterpillars feed on mistletoes so they most keep to the crowns of tall trees, but they often come down to feed on attractive flowers, especially Lantana.

Another example is the Citrus Butterfly (Papilio demoleus) (fig. 2) which you may sometimes see busily flying even through the two DTI Markets. This is one of the few species that has been helped by urbanization and deforestation. It used to be quite a scarce forest butterfly feeding on obscure Rutaceous plants, but it now feeds almost exclusively on lime, lemon, and orange foliage. So it has now established a completely new habitat in the gardens of suburbs like Gulshan and Dhanmondi; more than that it has also during this century established itself on Sumatra, Java, and as recently as the 1950s in the Philippines.

Butterflies come in all shapes and sizes. The smallest Grass Blue (Zizeeria hylax) has a wingspan of just over one centimetre; the two Great Mormons (Papilio memnon and P. polymnestor) have wingspans of well over fifteen centimetres. The little white Psyche (Leptosia nina) flutters weakly through the darker corner of gardens, so slowly that you can almost pick it out of the air with you fingers; by contrast, the large Black Rajah (Charaxes solon) flies like a rocket.

So go have a look for yourself. A butterfly walk is a nice way to pass a morning, but remember that butterflies are only active in warm sunlight; you will not see any on your early morning jog. Between 09.00 and 11.00 is best. Good places are the nurseries along Gulshan Lake (e.g. opposite the British High Commission); I have seen up to twenty species on a single walk. The Botanical Gardens is another nice place - not just for the butterflies but for natural beauty in general. And the Bhawal National Park half an hour north of the Airport is also good. The two last localities get very congested by lunchtime with huge picnics and ghetto-blasters at full volume. So get there early and get as far away from the main entrances as possible - or go on a non-weekend day.

So have a good butterfly walk. And when you do see that butterfly, please do marvel at the fact that it has managed to survive pollution and habitat modification that have killed off at least three-quarters of the original flora and fauna in the Dhaka area over the past 150-200 years.

Torben B. Larsen