Fig. 1. Micrographs showing stem internode tissues of maize hybrid 632 at full physiological maturity (mature grain, Sampling Date 10) remaining after in vitro degradation by rumen microbes for 24 or 96 h. The images were created by combining two adjacent fields of view. The double-ended arrow indicates the approximate width of the rind region that remained nondegraded. Bar = 500 µm; par, parenchyma; scl, sclerenchyma.