Fig. 6. 





<pA^^/f <^<9CA. 



(^Aa^/ sA^jT/^^ c//s/r//>u//&/^ a/ /"/g/r/s /ge^jn/ ///^J/ ^/aa^S c/ S>(<^/eJ . 





■i^CO 



.^^■f 



/krce/?/ofd^ x5ca/e o/' C/asses. 



