SUNFLOWER. STEM. 45 



2. The radicle protrudes, and curves downwards. 



3. The hypo-cotyledonary stem elongates, so that the 

 pericarp and testa are carried upwards by . the 

 cotyledons, which remain inclosed by them for a con- 

 siderable time. 



4. The coats of the fruit fall from the cotyledons, 

 which soon turn green, and expand as assimilating 

 leaves, with the plumule seated between them. 



5. The plumule develops leaves, which expand in 

 succession. 



6. The radicle has meanwhile elongated and produced 

 lateral roots. 



Notice that when the young root is removed from 

 the soil, many particles adhere to it, especially at some 

 distance from the apex ; these are held by the root- 

 hairs (cf. infra}, which attach themselves closely to the 

 particles of soil. 



The internal changes accompanying the process of germination 

 and more especially the redistribution of the reserve materials 

 stored in the embryo, may be studied by cutting sections of the 

 seedling at different stages of the process, and comparing the cell- 

 contents in the corresponding tissues. 



HERBACEOUS TYPE. 

 * Mature. 



Observations with the Naked Eye. 



I. Examine the whole of a well-grown plant of the 

 Sunflower. The main axis or Stem is stout, herba- 

 ceous, and erect : it often develops to a considerable 

 length without branching: it is cylindrical, slightly 

 striated below, while the higher parts of it, where the 



