8 NATURE TEACHING 



coats, owing to the fact that the soil did not hold down 

 the coats sufficiently firmly, so that they were pulled up 

 when the plant tried to draw out the cotyledons. Such 

 plants are often greatly hindered in their growth by the 

 presence of these no-longer-wanted coats. Cases such 

 as this should be borne in mind in attempting to dis- 

 cover what are the uses of spiny or warty coats of many 

 seeds. 



In some seeds, for example, scarlet runners, peas, and 

 acorns, the seed-leaves are not drawn out of the seed- 

 coats in the manner described, but remain below the 

 ground. The young stem makes its appearance above 

 ground in an arched form, but, in this case, the arch is 

 formed above the point of attachment of the cotyledons 

 to the plumule. The growth of the arch now merely 

 draws out the plumule with its tender leaves. The 

 young plant lives for some time on the store of food 

 in the cotyledons, which gradually become thin and 

 shrivelled, exactly as in the case of the French bean, 

 where, coming above ground, the changes in the cotyle- 

 dons are more easily watched. 



The seeds of the vegetable marrow and cucumber 

 exhibit interesting peculiarities in their germination. 

 The root makes its appearance first, and assumes the 

 curved or arched form in a similar manner to that of the 

 bean. The seed being flat, usually lies upon one side. 

 On the other side of the arch, and quite close to the 

 small hole through which the root makes its appearance, 

 there is formed a protuberance. This protuberance 

 catches the lower edge of the seed-coat and holds it 

 firmly against the soil. The cotyledons, still within the 



