EXPLANATION OF PLATE VI. 



Cylindrical mortar, found in 1861, with other relics of .stone, embed- 

 ded in auriferous grav^el about 10 feet beneath the surface, 3 miles 

 northeast of Shingle Springs. Eldorado County, Cal. Height, d inches; 

 diameter near top, T inches; at base, about 5^ inches. Conical pit 4^ 

 inches deep. The material is a rather soft talcoso rock, probably- 

 altered d\^ke material. The outlines are somewhat irregular, but the 

 surfaces are all artiticial. Referred to }}y Whitney, p. 205. This type 

 of mortar is not unusual in central California, but is apparently not 

 often found in use by the present tribes. No. 20. Voy collection. 

 434 



