FIGURE 4. Hypothetical transformation series represented by known fossil record of Mimomys (Cromeromys) and Lemmiscu m1s, shown as left side molars. 1–2: Mimomys hordijki, Zuurland, early Early Pleistocene, 1: LMB, no. Z3-201, type; 2: LBM, no. Z2-002; 3: Mimomys dakotaensis, Java, Early Pleistocene, type; 4–6: Mimomys virginianus, Early Pleistocene, 4: Hamilton Cave (after Repenning and Grady 1988, p.6, figure 1 D), 5–6: Porcupine Cave, 5: (after Bell and Barnosky 2000, p. 101, figure 4 D), 6: (after Repenning 2003, p. 506, figure 17.9, reversed); 7–8: Lemmiscus sp., Early Pleistocene, 7: Porcupine Cave (after Bell and Barnosky 2000, p. 113, figure 8 D, reversed), 8: SAM Cave (after Repenning 1992, p. 35, figure 6 F); Lemmiscus curtatus, Snake Creek Burial Cave, Late Pleistocene-Holocene (after Bell and Mead 1998, p.84, figure 1 B). Scale bar equals 1 mm.