360 ANNUAL, REPORT SMITHSONIAN INSTITUTION, 1923 



and Allactaga, the gerbils (Meriones), and the ground squirrel 

 {Gitellus). Here also are to be found the various members of the 

 hamster family, rats characterized by the presence of large cheek 

 pouches. Squirrels are universally distributed, characteristic forms 

 being the huge flying squirrels, David's squirrel, the fur squirrels, 

 and the chipmunks. The largest rodent in the country is the porcu- 

 pine (Hystrix) , which occurs throughout the Yangtse Valley and in 

 south and west China. 



Closely related to the rodents are the lagomorphs, or hares and 

 pikas. These used to be classed with the rodents, but are now looked 

 upon as belonging to a different order, whose development was, 

 nevertheless, closely parallel. There are numerous subspecies of the 

 common hare (Lepus swinhoei) in China north of the Yangtse. 

 South of that river occurs a totally different animal, namely the 

 Chinese hare (L. sinensis) . This is a rather unique distribution and 

 division of habitats, since the rim of the Yangtse basin and not the 

 river itself usually forms the boundary line between the ranges of 

 any two forms of animal in China. Apparently the Yangtse Eiver 

 has proved sufficient of a barrier to keep the one form to the south 

 and the other to the north, and this in spite of the fact that hares 

 are well known to be expert swimmers. 



The pikas (Ochotona) are really small hares or rabbits, and they 

 are confined to the north and the higher regions of the center and 

 west. Strangely enough they occur on the flat plains of Mongolia, 

 in the lowest ravines of Shensi and Kansu, in the forested areas 

 of Shansi, and also at the very summits of the highest mountain 

 ranges. This is evidently because they belong to a very old group 

 of mammals, and so have had a long period in the country in which 

 to spread and adapt themselves to all kinds of environment. They 

 once inhabited Europe, but became extinct there along with all the 

 other "steppe" animals. Now they are confined to certain parts 

 of Asia and North America. 



The bats and insectivores are two other groups of mammals that 

 are well represented in China, some very remarkable forms of the 

 latter occurring in the west. In the north hedgehogs and shrews 

 are fairly common, as also are certain forms of mole. One of the 

 most interesting of the Chinese insectivores is the peculiar Neote- 

 tracus sinensis from the west, which combines the characters of the 

 shrews and the hedgehogs. • 



Of apes and monkeys China does not boast a large number or 

 variety, though it is interesting to note that the most northerly repre- 

 sentatives of this great group of mammals in the world to-day are 

 to be met with in this country. In the area to the northeast of 

 Peking, known as the Tung Ling, the fine Chihli macaque still 

 occurs. In Ssuchuan the famous golden-haired monkey (Rhini- 



