PLATE LXXIII. 



Fig. 43. Cross section of the bark of a stem five years old: c, 

 cork; b, bast fibers; /, lignified tissue with the exception of the bast 

 fibers; u, unlignified tissue. X 41.5. 



Fig. 44. Cross section of bark: c, cork; j, parenchyma; b, bast fibers; 

 p, phloem; m, medullary ray. X 100. 



Fig. 45. Longitudinal section of the bark: c, cork; j, parenchyma; 

 b, bast fibers; m, medullary rays; p, phloem. X 100. 



Fig. 46. Cross section of bark: b, bast fibers; j, parenchyma; s, 

 stone cells; p, phloem; i, sieve plate. Stippling indicates lignified tissue. 

 X 277.5. 



Fig. 47. Longitudinal section of the bark. Lettering same as in fig. 

 46. X 555. 



Fig. 48. Bast fiber of medium length from the bark. X 277.5. 



