10 NATURE TEACHING. 



of the young plant. In those cases, however, 

 where there is a separate store of plant food, 

 that is in albuminous seeds, there must exist 

 some means whereby this food can be con- 

 veyed into the young plant. It will be well 

 to describe one or two examples showing how 

 this is accomplished. 



12. The onion has an albuminous seed. 

 In germination the young rootlet first makes, 

 its appearance, and, immediately afterwards, 

 there appears the lower portion of the coty- 

 ledon. This assumes the arched form as de- 

 scribed in the case of other seeds, the tip of 

 the cotyledon however is not withdrawn, but 

 remains for some time within the seed- coat 

 in contact with the supply of food stored 

 up there. Upon the portion of the cotyledon 

 in contact with this food there is formed, what 

 may be described as a sucker, an absorbing 

 organ, which takes up the stored food and 

 passes it on to the growing plant. When all 

 the food store has been absorbed the coty- 

 ledon is withdrawn from the seed-coat and the 

 young seedling becomes erect, the cotyledon 

 being now green and acting as an ordinary 

 leaf. 



13. A somewhat similar condition of things 

 is to be found in the germination of the seeds of 



