October 2007. The soil collected from places where butterflies, Catopsilia sp., mud-puddle in Chhattisgarh, India, is also used as traditional medicine. The question asked was, what is special about this soil?
The butterflies are likely "mud-puddling", looking for salts and other nutrients. Papilio demoleus (104545), Catopsilia sp. (possibly several species) (104546), and Hypolimnus sp. (104528), will be males, as salts sequestrated from the liquids ingested are transferred to the female during copulation.
See also: http://en.wikipedia.org/wiki/Mud-puddling