82 SQUIRRELS, MARMOTS AND PIKAS. 



A sub-species of 0. cansa has recently been described by Mr. 

 Thomas from the Tai-pei Shan in South Shensi, under the name of 

 0. c. viorosa. 



In the same district, yet another species has been newly described 

 by the same authority. This is 0. syrinx, and is related to 0. cansa, 

 but is much larger, and has smaller bullae. 



These eight species are all very much alike in external general ap- 

 pearance, the noticeable differences being mainly in their sizes and 

 different shades of colour. 



