256 GLIMPSES I\TO PLANT-LIFE 



In this earl)' stage these parts Hve entirely upon 

 the contents of the seed, just as a j'oung chick is 

 developed and nourished upon the albumen of the 



The temperature requisite for germination varies 

 according to the species ; those of us who possess 

 gardens know to our cost at what a low tempera- 

 ture such plants as chickweed, bittercress, ground- 

 sel, and some of the speedwells grow ; as long as 

 the thermometer is above freezing-point these 

 troublesome weeds will make their appearance in 

 our flower borders. Sach's experiments on germi- 

 nation tend to show that wheat and barley begin 

 to grow below five degrees centigrade, whilst 

 French beans and maize germinate at nine degrees 

 centigrade. 



Some plants start into growth very quickly. 

 Garden cress, vegetable marrows, and some grasses 

 appear above ground a few da)'s after they are 

 sown, whilst other seeds, enclosed in a hard, woody 

 seed-case, will require twelve months to germinate. 

 This was the case with a seed taken out of a cedar 

 cone brought from Mount Lebanon ; I xainl)' 

 watched for the j'oung plant, and when a )'ear had 



