EXPLANATION OP PLATE l^ll^.—Coniimied. 



Fig. 33. — From the pith of the root : young corpuscles collected 

 round the nucleus. 



Fig. 34. — From the same at a somewhat later stage : most of the 

 corpuscles contain minute starch-grains. 



Fig. 35. — From the same : the corpuscles, which have become rod- 

 shaped, bear triangular starch-grains. 



Fig. 36. — From the same : large starch-grains with corpuscles ; at 

 this stage the corpuscles are delicate, and can only be well seen after 

 treatment with iodine. 



Figs. 37, 38.— From the young colourless tuber: starch-formiug- 

 corpuscles bearing starch-grains collected round the nucleus. 



Figs. 39, 40. — From the same, at a later stage. 



Fig. 4L — From the same: the preparation has been treated with 

 iodine. The posterior end of the starch-grain is invested by a 

 gelatinous substance which only becomes visible after treatment with 

 iodine. 



Fig. 42. — From the apical portion of the tuber after it has become 

 green : the rod-shaped chlorophyll-corpuscles bearing small starch- 

 grains are collected about the nucleus. 



Fig. 43. — From the same : chlorophyll-corpuscles bearing starch- 

 graiiis. 



Fig. 44. — From the same : cortical cell containing chlorophyll-cor- 

 puscles and minute starch-grains. 



Fig. 45. — From the root which has become green: chlorophyll- 

 corpuscles bearing starch-grains. 

 Figs. 46 — 53. — From the pith and the cortical parenchyma of the rhizome 

 of Canna gigantea. 



Fig. 46. — Very young cell of the pith, with starch-forming-cor- 

 puscles. 



Fig. 47. — An older cell: the corpuscles now bear starch -grains. 



Fig. 48. — At a later stage : the corpuscles, which have become 

 swollen and somewhat elongated, are attached to the posterior ends of 

 the starch-grains. Li the swollen portion is a crystalloid, which only 

 becomes visible on treatment with water. 



Fig. 49. — An older starch-grain : the corpuscle forms a delicate 

 margin along its posterior border. 



Fig. 50. — From the rhizome after it has become green : nucleus, 

 and chlorophyll-corpuscles each containing a crystalloid, from a cell 

 of the inner cortex. 



Fig. 51. — From the same : chlorophyll-corpuscles and starch-grains 

 from the young pith. 



Figs. 52, 53. — From the same: |^chlorophyll-corpuscles from the 

 outer cortex. 

 Fig. 54. — From the rhizome of Canna discolor. 



Fig. 54. — Cortical cell, with spindle-shaped corpuscles containing 

 crystalloids (probably starch-forming corpuscles). 

 Figs, 55, 56.— From the etiolated stem of Begonia cucidlala. 



Fig. 55. — Leucophyll-corpuscles, bearing small starch-grains, col- 

 lected round the nucleus; from the apical portion. 



Fig. 56. — Leucophyll-corpuscles with large starch-grains. 



