LIST OF ILLUSTRATIONS 



FIG. PAGB 



1 Horse-bean 1 



2 Horse-bean opened 1 



3 Castor-bean 2 



4 Castor-bean opened 2 



5 Corn 3 



6 Corn cut lengthwise 3 



7 Sunflower seed 3 



8 Sunflower seed opened 3 



9 Peanut 4 



10 Peanut opened 4 



11 Arrangement for keeping: seeds on ice 5 



12 A bottle containing seeds, filled with water and corked air-tight 5 



13 A method of determining whether air-dry seeds contain water 7 



14 A bean placed in water, showing successive stages in the process of 



wrinkling 8 



15 A method of determining whether openings exist in the seed-covers .... 8 



16 An arrangement for holding seeds while under water 9 



17 A home-made balance constructed of umbrella wire 13 



18 A modification of the balance 14 



19 A method of keeping seeds half-submerged, in order to discover how 



the water enters 15 



20 Seed-covers floating on water 16 



21 Modification of the experiment shown in Fig. 20 19 



22 Scarlet Runner Bean opened, showing the pocket into which the caulicle 



fits 20 



23 Seeds half-submerged in wet sand, to determine how the water enters. . 21 

 23a Three rows of corn planted at the same time, each grain being half- 

 buried in the moist soil 22 



24 "Walnut divided in half, showing the wick-like central strand 23 



25 Seeds placed in a saturated atmosphere 26 



26 Another method of keeping seeds in a saturated atmosphere 27 



27 Method of maintaining a saturated atmosphere and a constant water- 



level 27 



28 Method of testing the permeability of the seed-cover to air 30 



(xiii) 



