related to the Myriopods, since their abdominal segments often bear appendages (Machilis). The Campodea-form appears in most of the Pseudoneuroptera [Libellulids, Ephemerids, Perlids, Psocids and Termes], Orthoptera, Coleoptera, Neuroptera, perhaps modified in the Strepsiptera [Stylops and Xenos] and Coccidae in their first stage of development, and indeed in many of these at their first moult." Farther on he says, "A larger part of the most highly developed insects assume another larva-form, which appears not only as a later acquisition, through accommodation with certain definite relations, but also arises as such before our eyes. The larvae of butterflies and moths, of saw flies and Panorpae, show the form most distinctly, and I call this the caterpillar form (Raupenform). That this is not the primitive form, but one later acquired, we see in the beetles. The larvae of Meloe and Sitaris in their fully grown condition possess the caterpillar form, but the new born larvae of these genera show the Campodea form. The last form is lost as soon as the larva begins its parasitic mode of life. * * * The larger part of the beetles, the Neuroptera in part, the bees and flies (the last with the most degraded maggot form) possess larvae of this second form." He considers that the caterpillar form is a degraded Campodea form, the result of its stationary life in plants or in wood. [Illustration: Pl 2. EXAMPLES OF LEPTIFORM LARVAE. EXPLANATION OF PLATE 2. Figure 1, different forms of Leptus; 2, Diplax; 3, Coccinella larva; 4, Cicada larva; 5, Cicindela larva; 6, Ant Lion; 7, Calligrapha larva; 8, Aphis larva; 9, Hemerobius larva; 10, Glyrinua larva; 11, Carabid larva; 12, Meloe larva.] [Illustration: Pl 3. EXAMPLES OF ERUCIFORM LARVAE. EXPLANATION OF PLATE 3. Figure 1. Panorpa larva; 2, Phryganea larva; 3, Weevil larva; 4, third larva of Meloe; 5, Chionea larva; 6, Carpet Worm; 7, Phora larva; 8, Wheat Caterpillar; 9, Sphinx Caterpillar; 10, Acronycta? larva; 11, Saw Fly larva; 12, Abia Saw Fly larva; 13, Halictus larva; 14, Andrena larva.] [Illustration: 204. Tipula Larva.] For reasons which we will not pause here to discuss, we have always regarded the eruciform type of larva as the highest. That it is the result of degradation from the Leptus or Campodea form, we should be unwilling to admit, though the maggots of flies have perhaps retrograded from such forms as the larvae of the mosquitoes and crane flies (Tipulids, Fig. 204).