Fig. 234.—White butterfly and young.
Fig. 235.—A butterfly which resembles a leaf.
In southern California, almost every spring, there is a migration of butterflies from the south northward along the Sierra Madre. I have watched them for hours, numbers being seen over a given spot every moment. By writing to postmasters and other persons in different sections, I found that the migrating band was two hundred miles long and from ten to twenty miles wide. Doubtless this was but a fraction of its actual extent, it being made up, in reality, of millions of yellow butterflies. Darwin saw such a migration in South America. Their pathway was several miles in width, they filled the air like a yellow cloud, and were several hours passing a given point. Vessels out at sea have met with similar flocks blown away from the shore.
Fig. 236.—Peacock butterfly.
Fig. 237.—Silkworm moth.
The butterflies are included in the Lepidoptera, and are the day-flying forms. There are many other insects equally beautiful, in more subdued tints, which are night flyers. These are the moths (Fig. 237), which are slow of flight, ponderous, and have extraordinary tongues for sucking the juices from the flowers. They can be distinguished from the butterflies by their feathered antennæ. One of the best known for its ravages is the dwarf moth, the worm of which plays such havoc among woolens. The cankerworm moth is equally a pest among valuable shade trees. Another familiar form is the hawk moth (Fig. 238), which so resembles a humming bird in appearance and motion that it is almost impossible to distinguish between the two, the moth being one of the most active, poising over flowers and inserting its enormous tongue to secure the sweets there concealed. A showy moth is the huge Attacus, its larva being especially large and voracious.
