176 



BULLETIN 75, UNITED STATES NATIONAL MUSEUM. 



FIG. 79. OPHIOCRASIS PICTYDISCA. a-c, X 7; d-g, ) 11. a, FROM ABOVE; (*,FROM BELOW; c, SIDE 



VIEW OF TWO ARM JOINTS NEAR DISK; d, A YOUNGER SPECIMEN, FROM ABOVE; < , THE SAMK, FROM 15ELO\V; 

 /. SIDE VIEW OF THREE ARM JOINTS NEAR DISK; (I . ANOTHER YOUNG SPECIMEN FROM ABOVE, SHOWING 

 THE INEQUALITY OF THE TWO TRIOS OF ARMS. 



