The first stage of a butterflys life cycle is the egg stage. The female butterfly lays tiny eggs, which are usually found on the leaves of plants. The size of the egg depends on the species of butterfly, but they are generally very small and oval, round, or cylindrical in shape. The eggs range in size from a period at the end of a sentence to the tip of a pencil. The eggs gestate for about a week or two, at which point they hatch into butterfly larvae or caterpillars.