6 PLANT PROPAGATION 
of transplanting, so that they can be removed without 
much injury to the roots after the soil has been loosened. 
Seed is often wasted and injury done by sowing too 
thickly, the resulting young seedlings when they come up 
being so crowded that there is not sufficient space for 
_ the free passage of light and air between them; conse- 
quently they run up weak and slender instead of being 
SEEDLINGS OF CEREUS. (Magnified Six Times.) 
a, One month after germination; 2, two months after germina- 
tion; c, three months after germination. 
sturdy and strong, and extra labour is required in 
thinning them out. 
Many seeds germinate much more regularly and 
rapidly by being subjected to a higher temperature than 
that in which the plants are to be grown, and are bene- 
fited by a slight bottom heat such as may be obtained in 
the propagating-house or by making a hotbed of litter 
