Electron micrographs show that Remak bundles form in sciatic nerves of adult control mice (A and B), but do not form in those of mutant mice (C and D). Quantitative analysis is shown in E. BoxedElectron micrographs show that Remak bundles form in sciatic nerves of adult control mice (A and B), but do not form in those of mutant mice (C and D). Quantitative analysis is shown in areas in A & C are shown in B & D, respectively. Stars, Remak bundles; Arrows, myelinated axons; Arrowheads, unsorted axonal bundles; SC, Schwann cells.