5. The section of the connectives appear to have no influence on nutrition, but affects reproduction, the attempt at fertilization on the part of the male producing no result, and the impregnated female laying no eggs. 6. Injury to the brain, or to the subœsophageal, or one of the thoracic ganglia, is followed by a momentary enfeeblement of the ganglion affected. Afterwards there results a convulsive trembling, which either pervades the whole body or only the appendages innervated by the injured ganglion. 7. As a result of an injury to the brain there is such a lack of steadiness in the movements that the insect walks or flies in a circle; for instance, a fly or dragon-fly thus injured in flying describes a circle or spiral. Steiner, in making this experiment, observed that the insect circled on its uninjured side. The brain is thus a motor centre. 8. By injuring a thoracic ganglion, one or all the organs which receive nerves from the ganglion are momentarily weakened. Afterwards the functions become restored. Sometimes, however, the insect walks in a circle. Faivre observed that after the destruction of the metathoracic ganglion of _Dyticus marginalis_ the hind wings and hind legs were partially paralyzed (Kolbe, _ex_ Yersin). LITERATURE ON THE NERVOUS SYSTEM _a._ General =Newport, George.= On the nervous system of the _Sphinx ligustri_ L., and on the changes which it undergoes during a part of the metamorphoses of the insect. (Phil. Trans. Roy. Soc., London, 1832, pp. 383–398; 1834, pp. 389–423, Pls.) =Helmholtz, H. L. F.= De fabrica systematis nervosi evertebratorum. Diss. in aug. Berolini, 1842. =Blanchard, E.= Recherches anatomiques et zoologiques sur le système nerveux des animaux sans vertèbres. Du système nerveux des insectes. (Annales des Sciences nat., Sér. 3, v, 1846, pp. 273–379, 8 Pls.) —— Du système nerveux chez les invertèbres dans ses rapports avec la classification de ces animaux. Paris, 1849. —— in Cuvier’s Règne animal. (Edition accompagnée de planches gravées. Insectes. Pl. 3, 3_a_, and 4.) =Leidy, Joseph.= History and anatomy of the hemipterous genus Belostoma. (Memoirs Amer. Acad. Arts and Sc., N. S. iv, 1849, pp. 57–67, 1 Pl.) =Scheiber, S. H.= Vergleichende Anatomie und Physiologie der Œstridenlarven. (Sitzungsb. k. Akad. wiss. Wien. Math.-Naturwiss. Cl., xli, 1860, pp. 439–496; xlv, 1862, pp. 7–68; 5 Taf.) =Tullberg, Tycho.= Sveriges Podurider. (K. Svenska vet. Akad. Handl. x, 1872, pp. 1–70, 12 Taf.) =Berlese, A.= Osservazione sulla anatomia descrittiva del _Gryllus campestris_ L. (Atti della soc. Veneto-Trentina, 1880, vii, pp. 200–299.) =Baudelot, E.= Contributions à la physiologie der système nerveux des insectes. (Revue d. sc. nat., i, pp. 269–280, 1872.)