Fig. 2. Aerobic recovery from anoxia in embryos of A. limnaeus exposed to anoxia for (A) 7, (B) 30 and (C) 60 days. Filled and open pairs of bars represent the number of embryos (out of a total of 20) initially surviving anoxia (filled) and those that resumed normal development after 1 week of aerobic recovery (open) from early development through diapause II (age of embryos given in days post-fertilization). Hatched and open pairs of bars represent the number of embryos initially surviving anoxia (hatched) and those that resume normal development (open) after 1 week of aerobic recovery as post-diapause II embryos. The stages of these embryos are given as days post diapause II. Bars are means ± s.e.m. (N=3). Asterisks over the open bars indicate a significant difference between initial survival of anoxia and survival after 1 week of aerobic recovery (paired t-test, P<0.05, one-tailed).