PLATE X. 



FlG. 26. Frequency of stomata on 1 sq. mm. of leaf surface of No. 

 4. X 67. 



Fig. 27. Cross section of midrib, No. 1 % length of leaf from base 

 of blade. Bast stippled; phloem, black; xylem showing water tubes. 

 X 23. 



Fig. 28. Cross section of midrib, No. 2, same position as in No. 1 

 (fig. 27), showing persistence of middle bundle, x 23. 



Fig. 29. Cross section of midrib of No. 3, same position as in No. 

 1 (fig. 27). 



Fig. 30. Cross section of midrib of No. 4, same position as in No. 

 1 (fig- 27). 



Fig. 31. Showing manner of ending of middle vascular bundle of 

 midrib in Nos. 1, 2, and 3; e, position of bundles immediately above 

 junction with vein; f, toii, stages in joining of middle bundle with upper 

 bundle. Bast, stippled; phloem, black; xylem, showing water tubes 

 (diagramatical) . 



Fig. 32. Modification of ending shown in fig. 31, also found in Nos. 

 1, 2, and 3. 



Fig. 33. Showing manner of ending of middle bundle of midrib in 

 No. 4. Middle bundle joining upper bundle at side. 



Fig. 34. Cross section of petiole at base of blade, No. 1. Bast, 

 stippled; phloem, black; xylem, showing water tubes; k, middle vas- 

 cular bundle. 



Fig. 35. Cross section of petiole of No. 2 at base of blade. X 23. 



Fig. 36. Cross section of petiole of No. 3 at base of blade. x 23. 



Fig. 37. Ci-oss section of petiole of No. 4 at base of blade. X 23. 



Fig. 38. Cells from seed of No. 1,. showing starch grains. X 255. 



Fig. 39. Cells from seed of No. 2, showing starch grains, x 255. 



Fig. 40. Cells from seed of No. 3, showing starch grains, x 255. 



Fig. 41. Cells from seed of No. 4, showing starch grains, x 255. 



Fig. 42. Stone cells, acorn cup. 



Fig. 43. Tracheids, acorn cup. 



Fig. 41. Stone cells from shell of acorn. 



