SOUTHERN CALIFORNIA ACADEMY OF SCIENCES 157 



The unit of value of this currency differed somewhat among 

 the different tribes ; with some it was a string of the length of 

 a man's arm, consisting of a certain number of long shells from 

 the end of the fingers to the elbow, and shorter ones above. 

 Such a string was formerly valued at from forty to fifty 

 Dollars in gold. With others, the standard of measurement 

 was a string of five shells, valued according to the length of 

 the shells. These were worth from ten to twenty-five dollars 

 in gold; or, from two dollars a shell for those of ordinary 

 length, to five dollars a shell for the longest. A wife could be 

 bought for from three to ten strings of alli-co-cheek. 



This dentalium money was also highly prized by the Indians 

 of the interior, and, as late as 1866, ten of these shells would 

 buy a superior buffalo robe. Among the Indians of Southern 

 California the Dentalium was used in a subordinate way, also ; 

 but the use of the "tusk-shells" (Dentaliums) as 

 money or ornaments was much less common than in 

 the extreme northern portion of the state. The shell- 

 money made from the columellas of some of the larger 

 univelve shells had a Dentalium imbedded in asphaltum at the 

 lower, or larger end, thus reducing the size of the opening to 

 make it correspond with the upper end or point of the shell 

 bead, to hold it in the proper position when strung with other 

 money. 



The Dentalium was, moreover, a very ancient inhabitant of 

 California ; for, in some rock recently brought from an altitude 

 of over 6,000 feet on the San Rafael Mountains, several speci- 

 mens of shells of this genus may be seen. They are also found 

 in other localities imbedded in rocks of cretaceous age. 



In Central California the shell money was largely manu- 

 factured from the shells of Saxidomus and Olivella. In South- 

 ern California, in addition to those named, quite a number of 

 other genera were used, principally the Tivela (Pachydesma) 

 crassatelloides, the "Big Clam" (See Fig. 4, PL 1). The 

 Tivela is a bivalve shell of large size, close texture, fine grain, 

 and ivory white color. It is found much larger than here 

 figured, and from one-fourth to nearly one inch in thickness. 



Amiantis (Callista) callosa, a somewhat similar shell, which 

 was used for the same purpose, is of finer grain and whiter 

 color. Beads or ornaments made from either of the two above 

 named species of shells can scarcely be distinguished from 

 bone or ivory, for which they are often mistaken. 



These represented the bullion from which the money was 

 manufactured, the shell being first cut or worked into suitable 

 size and form, then rounded and drilled (Figs. 5 to 14, PL 2). 

 How the aborigines managed to drill holes of the size and 



