These rodents have short, broad feet and a long tail. The first digit of both the hands and the feet is short and stumpy and has a flat nail. The other digits have short, slightly curved claws. The digit pads are large, and the sole of the hind foot is naked. The ears are moderately large, thin, and nearly naked.
Females usually have four mammae.
Pencil-tailed tree mice occur in forests and are primarily arboreal. It inhabits a variety of forest types and is especially common where there is bamboo. It is most active at night and spends the day in nests in hollow trees or the internodes of bamboo. To reach the internodal space of a standing bamboo stem, the mouse gnaws a circular hole 25 mm in diameter in the side of the internode. The opening is then lined with leaves.