Between the cells a reticulum is often to be seen, especially where the cells have burst; it extends between and among all the elements of the mucous lining, and probably serves, like the very similar structure met with in Mammalian intestines,[124] to absorb and conduct some of the products of digestion. Different epithelial cells may be found in all the stages noticed by Watney--viz., (1) with divided nuclei; (2) small, newly produced cells at the base of the epithelium; (3) short and broad cells, overtopped by the older cells around; (4) dome-shaped masses of young cells, forming “epithelial buds”;[125] (5) full-grown cells, ranging with those on either side, so as to form an unbroken and uniform series. The regeneration of the tissue is thus provided for. The cells come to maturity and burst, when new cells, the product of the epithelial buds, take their place. [124] See Watney, Phil. Trans., 1877, Pt. II. The “epithelial buds” described and figured in this memoir are also closely paralleled in the chylific stomach of the Cockroach. [125] These epithelial buds have been described as glands, and we only saw their significance after comparing them with Dr. Watney’s account. The epithelium of the chylific stomach is continued into the eight cæcal tubes, where it undergoes a slight modification of form. [Illustration: Fig. 67.--Section of Chylific Stomach, showing the six bundles of Malpighian tubules. × 70.] At the hinder end of the chylific stomach is a very short tube about half the diameter of the stomach, the small intestine. At its junction with the chylific stomach are attached, in six bundles, 60 or 70 long and fine tubules, the Malpighian tubules.[126] The small intestine has the same general structure as the œsophagus and crop; its chitinous lining is hairy, and thrown into longitudinal folds which become much more prominent in the lower part of the tube. The junction of the small intestine with the colon is abrupt, and a strong annular fold assumes the character of a circular valve (fig. 68). [126] Development shows that these tubules belong to the proctodæum, and not to the mesenteron. [Illustration: Fig. 68.--Junction of Small Intestine with Colon. × 15.] From the circular valve the colon extends for nearly an inch. Its diameter is somewhat greater than that of the chylific stomach, and uniform throughout, except for a lateral diverticulum or cæcum, which is occasionally but not constantly present towards its rectal end. The fore part of the colon is thrown into a loose spiral coil. A constriction divides the colon from the next division of the alimentary canal, the rectum.