. Embryology of insects and myriapods; the developmental history of insects, centipedes, and millepedes from egg desposition [!] to hatching. Embryology -- Insects; Embryology -- Myriapoda. 294 EMBRYOLOGY OF INSECTS AND MYRIAPODS located at the tip of the stomodaeal invagination, however these cells may be interpreted. In the genus Xenos, according to Hoffman (1913), cells from the proctodaeum also contribute to the building up of the mid-gut epithelium. When the dorsal organ is much reduced and the dorsal wall closes, the caudal end of the body tends first to straighten (Fig. 232) and then to
. Embryology of insects and myriapods; the developmental history of insects, centipedes, and millepedes from egg desposition [!] to hatching. Embryology -- Insects; Embryology -- Myriapoda. 294 EMBRYOLOGY OF INSECTS AND MYRIAPODS located at the tip of the stomodaeal invagination, however these cells may be interpreted. In the genus Xenos, according to Hoffman (1913), cells from the proctodaeum also contribute to the building up of the mid-gut epithelium. When the dorsal organ is much reduced and the dorsal wall closes, the caudal end of the body tends first to straighten (Fig. 232) and then to curve ventrad, so that finally the dorsal surface of the body is directed outwardly (Fig. 233). In the stage shown in Fig. 233 the communication between the mid-gut (ventriculus) and the vesicle-like hind-gut is not yet stom. neurp Fig. Dorsal closure. 232.—Stylops. organ, {drc) {br) Brain. {do) Definitive dorsal igc) Germ cells, {mge) Mid-gut epithelium, (nc) Nerve cord, (neurp) Neuropile. (proct) Proctodaeum. (stom) Stomodaeum. (y) Yolk. i^eurp / rnge y Fig. 233.—Stylops. (br) Brain, (gc) Germ cells, {mge) Mid-gut epithelium. (neurp) Neuropile. (p) Thoracic legs (dot- ted), (proct) Proctodaeum. (stom) Stomo- daeum. (y) Yolk. established. It is probable that the intestine remains imperforate. The development of the mesoderm, which is but feebly represented in Stylops, was not studied by Noskiewicz and Poluszynski (1927). The Alfalfa Snout Beetle (Brachyrhinus ligustici) The alfalfa snout beetle {Brachyrhinus ligustici) is an introduced species which probably came about forty years ago from central Europe where it is widely distributed. The adult is wingless, which probably accounts for the fact that it has spread so slowly. However, it multiplies in very large numbers in small, restricted areas and does serious damage to alfalfa. It develops parthenogenetically, males not having been found in the United States. The egg is in most cases oval in shape but sometimes almost s
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