THE SEED, GERMINATION AND THE PLANTLET 27 



unable to burst the seed-case, hence germination cannot 

 take place unless assisted by the expanding power of 

 frost, or long exposure to moisture which softens the seed- 

 case, or unless the seed-case is cracked before the seeds 

 are planted (36). 



Fig. 8. 



Fig. 9. 



Fig. 10. 



Fig. 11. 



Fig. 8. — Plantlet of pumpkin. Fig. 9. — Plantlet of bean. 



Fig. 10. — Plantlet of Indian corn. Fig. 11. — Plantlet of pea. 



In the pumpkin and bean, thie seed-leaves (cotyledons) are lifted above 



the surface of the soil in germination. 

 In the pea, the cotyledons are not lifted above the surface of the soil in 



germination. 



44. The roots promptly start, as the hypocotyl emerges 

 from the seed-case — the main (primary) root from its 

 point, and the branch (lateral) roots from its side. Some- 

 times root-hairs (100) may be distinctly seen, especially 

 when seeds germinate in the seed-tester (38) . 



By studying Figs. 8 to 11, we may learn more of the 

 germinating process. 



