Evils op Deep Sovtino. — In many seeds, the vital principle is so strong, that to scatter 

 them upon the soil is sufficient to insure their speedy germination ; but in others, the power 

 of growth will only manifest itself under more favorable conditions. Moisture is necessary, 

 but not an unlimited quantity ; if a seed is thrown into water, and cxi)Osed to a proper tem- 

 perature, the act of geniiination will take place ; but, unless the jilant is an aquatic, it will 

 speedily perish ; no doubt, because its powers of respiration are impeded, and it is unable 

 to decompose the water it absorbs, which collects in its cavities, and becomes putrid. There 

 must, therefore, be some amount of water, which, to the dormant as well as the vegetating 

 plant, is naturally more suitable than any other ; and experience shows, that quantity to be 

 just so much as the particles of earth can retain around and among them by the mere force 

 of attraction. To this is to be ascribed the advantage derived from those mixtures of peat, 

 loam, and sand, which gardeners prefer for their seedlings ; the peat and sand, together, 

 keep asunder the particles of loam which would otherwise adhere, and prevent the percola- 

 tion of water ; the loam retains moisture with force enough to prevent its passing off too 

 quickly through the wide interstices of loam and peat. 



Under what depth of earth seed should be buried, must always be judged by experience ; 

 but it should be obvious that minute seed, whose powers of growth must be feeble in pro- 

 portion to their size, will Ijear only a very slight covering, while those of a larger size, and 

 more vigor, will be capable, when their vital powers are put in action, of upheaving consider- 

 able weights of soil. As the extent of this power is usually uncertain, the judicious gardener 

 will take care to employ for a covering no more earth than is really necessary to preserve 

 around his seeds the requisite degree of darkness and moisture. An erroneous opinion 

 prevails that seeds must be "well" buried, in order that the young plants may have 

 " sufficient hold of the ground." But a seed, when it begins to grow, plunges its roots down- 

 wards, and throws its stem upwards from a common point, which is the seed itself; and, 

 consequently, all the space that intervenes between the surface of the soil and the seed, is 

 occupied by the base of the stem, and not by the roots. The seeds of the Araucaria illus- 



Oermination of Araucaria imbricata; a, the seed after it has inserted its radicle in the soil, the stem and leaves 

 just appearing ; b, the same seed, at a later period, firmly fixed in the ground by its roots. 



