MORPHOLOGY 



comes out first, through the pit mentioned in the last 



chapter, and begins to elongate and push its way 



downwards into the soil. Subsequently the plumule 



breaks its way through the testa and 



begins to elongate and grow upwards 



in the air. The radicle gives rise to 



the first or primary root, known as the 



TAP-ROOT, and the plumule gives rise 



to the first or primary stem or shoot, 



the two together forming the axis of 



the seedling. Soon the primary root, 



as it elongates downwards, gives off 



secondary or lateral branches from its 



sides in succession or acropetal 



order. The primary stem also, as it 



elongates upwards in the air, gives 



off branches in acropetal order like 



the primary root; and, 



in addition, leaves 



on its sides, also in 



the same order. 

 In Rice the radicle 



does not elongate 



into a tap-root, but 



a number of thread- 

 like roots burst out 



of it, forming a 



bunch known as a 



FIBROUS root (fig. 



lo). The plumule 



also grows into 

 a stem with leaves but no branches 



The mode of germination of the dicotyledonous 

 seeds agrees in all respects with that of the Gram, 

 and that of monocotyledonous seeds with that of 



J. lo. — Sprouting: 

 Seed of Rice 



Fig:. II.— Oryza sativa 



«, Germinating seed, 

 h, Fibrous root. 



(fig. II). 



