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 The abdomen in various species consists of from five to eleven overlapping rings with their foldlike joints between them. Does each ring overlap the ring in front or the one behind it?

The food tube (Fig. 127) begins at the mouth, which usually contains salivary glands (4, Fig. 127). What is the color of the grasshopper's saliva? The food tube expands first into a croplike enlargement; next to this is the stomach (6, Fig. 127), which resembles the gizzard in birds, as its inner wall is furnished with chitinous teeth (b, Fig. 114). These reduce the food fragments that were imperfectly broken up by the biting jaws before swallowing. Glands comparable to the liver of higher animals open into the food tube where the stomach joins the small intestine. At the junction of the small and large intestine (9) are a number of fine tubes (8) which correspond to kidneys and empty their secretion into the large intestine.

Key in text. Compare with Fig. 114.

The breathing organs of the insects are peculiar to them (see Fig. 128). They consist of tubes which are