Wild adult females of C. pipiens fatigatis in Rangoon exhibit a distinctive green coloration on emergence. The color can be seen through non-dorsal areas of the integument. It persists for about 2 and 3 days respectively, in the thorax and abdomen. Excretion, or egestion, or both, of green material partly accounts for the loss of color in unfed nullipars. Green unfed females are nulliparous, permitting simple age grading without dissection. Green color also occurs in freshly-laid egg rafts, fourth-instar larvae, and the ovaries of gravid females. Some wild engorged females have green-colored thoraxes, indieating feeding can begin within 48 hr after emergence.