Fig. 1. — Showing cross section of Carolina i)oi)lar (I'opiilus deltoides Marsli). 1, Cross 

 section of normal stem, enlarged; 2, same, showing abnormal growth; A, naked-eye 

 view of same; 4, section of a normal stem; 5, cross section of trunk of tree showing 

 the splitting of the hark; <i, bark; b, cork cambium; c, cortex; d, uhloeni; c, abnor- 

 mal parenchyma; ./; cambium; </, wood or xylem. 



