308 Blodgett : Vegetative Reproduction 



than the next preceding one, thus the five " seeds " of 1899, become 

 " 5 plumule-bulbs " in 1900, giving a total of 75 plants in 1903. 



1899 1900 1901 1902 1903 



5 seeds 5 seeds 5 seeds 5 seeds 5 seeds 



5 plumule-bulbs 5 plumule-bulbs 5 plumule-bulbs 5 plumule-bulbs 

 5 yearlings 5 yearlings 5 yearlings 



15 2 years old 15 2 years old 



45 flowers 



Total 75 plants 



There is very little chance that there will be forty-five blossoms 

 at the end of five years, but as some of the bulbs will probably 

 flower then it is convenient to call the entire number by one name, 

 when they are of the same crop or age. 



The seed resembles that of Iris in structure.* The walls of 

 the cells are thickened ; at certain points the walls of adjacent 

 cells retain their normal thin nature, so that a thin membrane 

 only separates the cell cavities. The cells are arranged with 

 their longer axes nearly perpendicular to the surface of the seed, 

 and in this way form lines which extend to the central portion of 

 the endosperm. Through the center of the seed a mass of dense 

 reserve cellulose extends (Fig. 19) with a few cell cavities scattered 

 through it. In the apex of the seed, and at the beginning of this 

 mass of dense material lies the embryo (Fig. 20). At germination 

 the embryo elongates, pushing the tip of the cotyledon along the 

 center of the seed, absorbing the dense cellulose as it advances. 

 From the cavity thus formed in the center, the solvent action ex- 

 tends toward the surface of the seed, following the lines of the 

 cells, and producing a honey-comb effect (Fig. 8). This honey- 

 combing is the more easily produced on account of the cell 

 arrangement which in a longitudinal section appears as in Fig. \Z,a; 

 in a horizontal one, as at b. The thin wall separating the depres- 

 sions in the thickened walls of adjacent cells readily dissolves under 

 the action of the absorbing gland of the cotyledon, thus opening 

 a passage for the movement of food materials from cell to cell, as 

 the solvent action extends. The dissolved material moves along 

 the channels so made toward the tip of the cot}'ledon. The ab- 

 sorbing organ (Fig. 6, g) is quite similar in structure, and probably 



* Haberlandt, Pflanzen Anatomie, 298. 



