236 THE FAUNA OF THE CHINESE PROVINCE 



Microtus are also common in this tract, which is also the habitat of one of the 

 zokors or the mole-voles (Myotalpa fontanieri). Zokors, which inhabit central and 

 north-eastern Asia, are members of the mouse tribe which lead a burrowing life, 

 and although nearly allied to lemmings, are almost identical in appearance with 

 the mole-rat. Both have the same curious flattening of the head and rounding of 

 the muzzle which give to the mole-rat its remarkable physiognomy, and in both the 

 eyes are rudimentary and the external ears wanting. Indeed, the likeness between 

 a zokor and a mole-rat, if we except the more powerful front claws of the former, 

 is much greater than that between a swift and a swallow. Till recently zokors 

 were generally known to zoologists by the name of Siphneus, but it is now the 

 fashion to replace that term by Myotalpa. Very noticeable is the occurrence in 

 north-eastern Asia of a representative of the jumping-mice (Zapus) of North 

 America. American affinities are also displayed by the occurrence in Japan of the 

 mole-like Urotrichus talpoides, a near relative of the North American Neiirotriclms 

 gibbsi. Quite recently another peculiar generic type, Scapanulus oweni, allied to 

 the American Scapanus, has been discovered in Kan-su. The Japanese Dymecodon 

 and the Sze-chuan Scaptonyx are also mole-like types peculiar to this region. 



The scattered distribution of the members of the Insectivora and the remote 

 corners of the earth in which many of them are found afford conclusive evidence 

 of the antiquity of this primitive and waning group of mammals. Additional 

 evidence of this is afforded by the discovery in Sze-chuan of a member of the group 

 which has been named Neotetracus sinensis, the name being intended to suggest 

 affinity with the small and imperfectly known Tetracus nanus of the French 

 Miocene. The smallest member of its group, Neotetracus is nearly related to the 

 Malay Gymnura and Hylomys, and the Philippine Podogymnura ; but while 

 approximating to the last in external characters, and especially the well-developed 

 tail, it agrees with the hedgehogs in the character and number of teeth and likewise 

 in the presence of vacuities in the palate, so that it forms a kind of connecting link 

 between the Gymnurincs and Erinaceinw. In size the Sze-chuan species may be 

 compared roughly to a half -grown rat ; but the general colour of its coat is reddish 

 yellow. 



The Japanese dancing mouse is widely spread in China and Japan, and differs 

 from ordinary mice in several structural details. That its original home was 

 China seems to be demonstrated by the fact that it was formerly known in Japan 

 by the name of Nankin Nesumi, meaning the mouse from Nankin. Perhaps the 

 most important difference between the dancing and ordinary mice is to be found in 

 the structure of the internal ear, in which there are several peculiarities, notably the 

 larger size of the so-called crystalline otoliths. In size the dancing mouse is smaller 

 and of lighter build than the house mouse, besides being of a more delicate consti- 

 tution. The dancing mouse, moreover, has a shorter tail with much fewer rings of 

 scales, and in this respect it resembles Wagner's mouse (Mils wagneri) of China, a 

 species allied to M, musculus, but with a shorter tail. Wagner's mouse is found not 

 only in China but also in southern Russia, while in central Asia it takes the place 

 as a semi-domesticated species of the ordinary house-mouse of Europe. The con- 

 clusion arrived at is that the dancing mouse is a variety of Mus wagneri, originally 

 domesticated in China, whence it was carried first to Japan, and then to Europe. 



