212 AGRICULTURE. 



Directions: For this purpose, use shallow boxes — 

 about four inches in depth — which have been soaked 

 in lime-water, or water containing a little formaldehyde, 

 or whitewashed. 



{a) Fill these with a soil prepared by carefully mixing 

 equal parts of sand, leaf-mould, and garden loam. Well- 

 rotted manure may be substituted for leaf-mould, and 

 rotted sod, cut up fine and sifted, for leaf-mould and loam. 

 It is well to add to this a very small quantity of wood 

 ashes. Sow the seeds on the surface of the soil and press 

 them in. 



(d) Apply moisture by very lightly sprinkling with a 

 small sprinkler or by hand. Cover with window-glass, 

 providing for the admission of air. 



(c) As soon as true leaves are well formed, they may 

 be transplanted into inch pots, and repotted into larger- 

 sized pots as often as is necessary. Before planting in 

 the open ground the plants should be hardened in a 

 cold frame (see under " Cuttings "). 



V. Variation of Plants. 



Though the offspring of plants is like the 

 parent in kind, yet individual members of the 

 species are not exactly alike. Their differ- 

 ences are often scarcely perceptible; but if 

 various members of the same species in a given 

 locality be compared, shades of differences may 

 be seen. For example, the little spring beauty 

 {Clatonia virginica) shows much variation in 

 the number and size of its petals. Their color 

 also ranges from white to deep pink. The dog's- 

 tooth violet {^ErytJironiiiiu albiduni) shows like 

 morphological differences. 



Throughout nature these variations exist, the 

 offspring differing from its progenitor. Among 



