The anatomy and histology of the alimentary tract of the grasshopper, melanoplus differentialis Thomas

Abstract

Abstract This investigation is intended to be the first of a contemplated series to study correlation of diet with morphological change. The material here reported is from grasshoppers on satisfactory diets. The gross anatomy shows a typically acridine arrangement. Fixation with B3 and staining with haematoxylin and eosin shows that peritoneum, muscle and chitin in different areas vary only in arrangement and relative development. The epithelial cells of the various regions differ in structure as well. Modifications of the cytoplasmic elements of these cells are correlated with cellular activity. The epithelial cells of the mid‐gut and its six bi‐lobed gastric caeca, and of the six rectal glands have a striated border of separate filaments which are cilia‐like in appearance but devoid of motion. The caeca are most active in gastric secretion, which is merocrine or holocrine according to conditions. Essentially different granules and vacuoles are secreted, and extruded by rupture of the cells; which are replaced from nidi.