The general characteristics of the pupae in these two sections have already been described.
In the Orthorrhapha, in the pupae of which the appendages of the perfect insect are usually visible, the pupa-case generally splits in a straight line down the back near the cephalic end; in front of this longitudinal cleft there may be a small transverse one, the two together forming a T-shaped fissure.
He carefully studied also the history of the ant and was the first to show that what had been commonly reputed to be "ants' eggs" are really their pupae, containing the perfect insect nearly ready for emersion, whilst the true eggs are far smaller, and give origin to "maggots" or larvae.
In cases where the disease is odourless the larvae are attacked after the cells are sealed over, and just before they change to pupae, when they become slimy, sputum-like masses, difficult to remove from the cells.
Fusca and other species, and carry off to their own nests pupae from which workers are developed that live contentedly as slaves of their captors.