Feb., 1912. 



Jade. 



i93 



jade seals do not differ from those of the metal ones; in fact, they are 

 derived from them so that they must be treated in connection with 

 this subject. Wu Ta-ch'e'ng has figured also a number of interesting 

 jade seals of the Mongol period engraved with Tibetan and Mongol 

 characters, the latter of the so-called "square" form (P'ags-pa) which 

 I shall deal with in another place. 



