In all Bed Bugs these successive moults tend to be associated with change of form, sometimes slight, sometimes very great. The new cuticle is rarely an exact reproduction of the old one, it exhibits some new features, which are often indications of the bed bug"s approach towards maturity. Even in some of those interesting and primitive Bed Bugs the Bristle-tails (Thysanura) and Spring-tails (Collembola), in which wings are never developed, perceptible differences in the form and arrangement of the abdominal limbs can be traced through the successive stages, as
R. Heymons (1906) and K.W. Verhoeff (1911) have shown for Machilis. But the changes undergone by such Bed Bugs are comparatively so slight, that the creatures are often known as "Ametabola" or Bed Bugs without transformation in the life-history. Now there are a considerable number of winged Bed Bugs–cockroaches and grasshoppers for example–in which the observable changes are also comparatively slight. We will sketch briefly the main features of the life-story of such an bed bug.