—— Beiträge zur Kenntniss der Farbe von Insektenschuppen. (Zeits. f. Wissens. Zool., lvii, pp. 306–384, 1893.) =Griffiths, A. B.= Recherches sur les couleurs de quelques insectes. (C. R. Acad. Sc. Paris, cxv, pp. 958, 959.) =Mayer, Alfred Goldsborough.= On the color and color-patterns of moths and butterflies. (Proc. Bost. Soc. Nat. Hist., xxvii., March, 1897, pp. 243–330, 10 Pls. See also p. 201 under Mayer.) Also the writings of Bates, Beddard, Belt, Butler, Darwin, Dimmock, Dixey, Eimer, Haase, Higgins, Müller, Poulton, Seitz, Wallace, Weismann. 2. INTERNAL ANATOMY THE MUSCULAR SYSTEM In its general arrangement the muscular system of insects corresponds to the segmented structure of the body. Of the muscles belonging to a single segment, some extend from the front edge of one segment to that of the next behind it, and others to the hinder edge; there are also sets of dorsal and ventral muscles passing in an oblique or vertical course (Figs. 16–18). As Lang observes, “the greater part of the muscles of the body can be traced back to a paired system of dorsal and ventral intersegmental longitudinal muscles.” The muscular system is simplest in larval insects, such as caterpillars, where the musculature is serially repeated in each segment. In the larva of Cossus Lyonet found on one side of the body 217 dorsal, 154 lateral, 369 ventral, and in the thoracic legs 63, or 803 muscles in all. “Adding to this number the 12 small muscles of the second segment, and 8 others of the third, which he did not describe, there would be for all the muscles on one side of the caterpillar 823. This would make for the entire body 1646, without counting a small single muscle which occurs in the subdivision of the last segment,” and also those of the internal organs as well as those of the head, so that the total number probably amounts to about 2000, not 3000, as usually stated in the books. Lubbock admits that Lyonet was right in his mode of estimating the number. In the larva of _Pygærci bucephala_ he found that “the large muscles scarcely vary at all,” though certain smaller ones are very variable. Lubbock observed that certain of the longitudinal muscles in the caterpillar of Diloba split up into numerous, not less than ten, separate fascicles. “This separation of the fibres composing a muscle into separate fascicles is carried on to a much greater extent in the larvæ of Coleoptera. Of course in the imago the number of thoracic muscles is greatly increased, or at least in Dyticus and the wood-feeding Lamellicorns, which alone I have examined. In these two groups each of the larger muscles is represented by at least twenty separate fascicles, which makes it far more difficult to distinguish the arrangement of the muscles.”