WALTZING MOUSE (or Japanese Waltzing Mouse), a pied race of the house mouse (H us musculus ), or one of its allies, originally bred in China, and known in Japan as the Nankin mouse. The habit of these mice of spinning round and round after their tails is highly developed, and continually exercised. In Japan, where there were originally two breeds, a grey and a white, these mice are kept in cages on account of their dancing propensities. The dancing was at one time supposed to be due to a disease of the labyrinth of the ear; but Dr K. Kishi, in a paper in the Zeitschrift fiir wissenschaftliche Zoologie (vol. xxi. pt. 3), concludes that it is the effect of confinement for untold centuries in small cages.