The butterflies arranged together under the above name are, in many
respects, the most remarkable of any to which our attention has yet
been directed. In size they are superior to all the other diurnal
lepidopterous tribes, except the _Ornithoptera_, and many of them rival
even that conspicuous group in their dimensions. Although surpassed by
many others of their tribe in elegance of form and harmonious blending
of colours, they afford examples of as rich tints as are to be found
in any other natural objects. The blue which adorns the whole surface
of _M. Menelaus_ and _Adonis_, has a beauty and lustre which it is
impossible to witness without admiration. When flying under the blaze
of a tropical sun, the brilliancy of the surface, as contrasted with
the dark hue of the under side, as they are alternately displayed, must
render them very striking objects. Most of them are from South America,
but a few occur in the eastern parts of India and the great islands of
the adjacent Archipelago.
The generic characters are more determinate than is the case with many
others of this order. The antennæ are slender, linear throughout their
whole length, or thickening so insensibly towards the extremity as
to deviate but slightly from that shape. The palpi are placed close
together, ascending, and clothed with scales, the terminal portion
narrow and very much compressed: abdominal margin of the inferior
wings curved downwards, and forming a deep groove for receiving the
body. Discoidal cell of the posterior wings open behind; claws bifid.
The caterpillars vary in form, as well as the chrysalides, and may
probably, if more fully known, enable us to subdivide this family into
more natural groups.