Oc. Papers, Cal. Acad. Sci., \'ol. X 



I Van Denburi.hI 



Pl,ATE 31 



o .5- 

 o S'l 



o 



C ^ ^^' 



< o 



o *■- 

 J= o 



0; 



Ol o 





-2 =;.2 



2 •= c 

 5 =" 



5: <^ d 



