708 APPENDIX. 



destroyed by exposing the seeds in thin layers in the open air during severe frosts ; 

 a practice common among seedsmen with all seeds which are above a year old. 



863, in p. 405. When it is wished to see the fruit of young seedlings, without 

 waiting till the plant comes to maturity, it may be effected by inserting a bud 

 near the extremity of one of the branches of a wall-tree of the same species, 

 in full bearing, and clearing away most of the other blossoms around to give it a 

 fair trial. 



868 in p. 407. The common single daisy, when brought from the fields, and 

 planted in a rich soil in the garden, becomes double. I have seen even the dimi- 

 nutive Sagina procumbens become double by cultivation. The improvement on 

 single dahlias from cultivation in rich soil is of recent date. When any of these 

 is neglected, as when the double-daisy edging is allowed to stand long and exhaust 

 the soil, it gets single ; and the want of cultivation causing double dahlias and 

 other flowers to assume the single state may be seen every season. An old root 

 of a dahlia allowed to stand on the same piece of ground, without manuring, and 

 to accumulate a number of stems, seldom produces full flowers. Mr. Munro's is 

 an instance in point ; but it is not two kinds of sap, but a more highly organised 

 state, and a crude unelaborated state, of the same sap. When the quantity of sap 

 is great, as in young and vigorous plants, flowers are seldom at all produced, till 

 the process of growing, by extending the system of leaves and branches, has pro- 

 duced the proper balance. The plant, which formerly had more sap than its 

 chemical and vital powers could elaborate into the highly organised state required 

 for producing fruit, having now acquired more strength, becomes fruitful ; and, 

 exhausted by its fruit-bearing, generally continues fertile, unless deluged again with 

 too much food, in the shape of manure. Such plants as fruit-trees in which the 

 fruiting state, or state of maturity, is brought about with difficulty, at a lengthened 

 period of years, are seldom found to produce double flowers. In those plants, 

 however, in which the flowering state is produced annually, double flowers are 

 more frequent. The different parts of the flower also differ as to the state of 

 organisation in the food required to feed them. Calyx, corolla, stamens, and pistils, 

 are only more highly organised states of leaves, or what would have been leaves ; 

 and each, in the order they are mentioned, continues to be more highly organised 

 than the preceding. In the ordinary mature state of the plant, with a sufficiency 

 of properly organised food, the germs of these parts of the flower will be produced 

 in the normal manner ; but if an over-supply of food, or of water to carry the food 

 to the absorbent vessels of the root, should ensue, the condition of the food may be 

 altered ; from a highly organised condition it may be lowered nearer to the compa- 

 ratively crude state required for leaves. In this state it is obvious that the germs 

 which would have started in the form of pistils and stamens may be lowered, for 

 want of proper food, to the inferior condition of petals, or even of leaves. When 

 the branch is highly gorged with unelaborated sap, the pistil may even again 

 assume the state of a terminal bud, and lead away a young shoot from the centre 

 of the flower, as is often seen to be the case in roses and other flowers. The above 

 appears to be the theory of double flowers most consonant to experience, it matters 

 not whose it may be ; and it agrees with all observation, that a luxuriant supply of 

 food is the cause of this monstrosity. It is also apparent, that, the farther we 

 reduce the supply of food, it will be the more easy again to gorge the plant which 

 has been starved, and produce monstrosity. If the seed has an extra vigour of 

 itself, it may produce so large an absorbent system of roots as may enable it, in a 

 rich state of the soil, to gorge the flower and produce monstrosity, from an ordi- 



