Chap. XXIII. CONDITIONS OF LIFE. 273 



forms, inhabiting two countries, such as North America and 

 Europe, which do not differ greatly in climate, nature of soil, &c, 

 for in this case natural selection will inevitably and rigorously 

 have acted during a long succession of ages. 



From the importance of the difficulty just alluded to, it will be advisable 

 to give as large a body of facts as possible, showing that extremely slight 

 differences in treatment, either in different parts of the same country, or 

 during different seasons, certainly cause an appreciable effect, at least on 

 varieties which are already in an unstable condition. Ornamental flowers 

 are good for this purpose, as they are highly variable, and are carefully 

 observed. All floriculturists are unanimous that certain varieties are 

 affected by very slight differences in the nature of the artificial compost in 

 which they are grown, and by the natural soil of the district, and by the 

 season. Thus, a skilful judge, in writing on Carnations and Picotees, 1 

 asks "where can Admiral Curzon be seen possessing the colour, size, and 

 " strength which it has in Derbyshire? Where can Flora's Garland be 

 " found equal to those at Slough ? "Where do high-coloured flowers revel 

 " better than at Woolwich and Birmingham ? Yet in no two of these 

 " districts do the same varieties attain an equal degree of excellence, 

 " although each may be receiving the attention of the most skilful culti- 

 " vators." The same writer then recommends every cultivator to keep 

 five different kinds of soil and manure, " and to endeavour to suit the 

 " respective appetites of the plants you are dealing with, for without such 

 " attention all hope of general success will be vain." So it is with the 

 Dahlia : 2 the Lady Cooper rarely succeeds near London, but does admirably 

 m other districts; the reverse holds good with other varieties; and again 

 there are others which succeed equally well in various situations A skilful 

 gardener 3 states that he procured cuttings of an old and well-known 

 variety (pulchella) of Verbena, which from having been propagated in a 

 different situation presented a slightly different shade of colour; the two 

 varieties were afterwards multiplied by cuttings, being carefully kept 

 distinct; but in the second year they could hardly be distinguished and 

 in the third year no one could distinguish them. 



The nature of the season has an especial influence on certain varieties 

 ot the Dahlia : m 1841 two varieties were pre-eminently good and the 

 next year these same two were pre-eminently bad. A famous amateur * 

 asserts that m 1861 many varieties of the Eose came so untrue in <Z 

 racter, "that it was hardly possible to recognise them, and the thought 

 was not seldom entertained that the grower had lost his tallv" Sh« 

 same amateur" states that in 1862 two-thirds of his Auriculas nroduoS 

 central trusses of flowers, and these are remarkable from not keeping true 



> 'Gardener's Chronicle/ 1853, p. a Mr. Kobson, in ' Journal of Horti^ 



f culture,' Feb. 13th, 1866 p 122 



» Mr. Wildman, < Floricultural Soc,' 4 « Journal of H orticu ture ' 1861 „ 



Feb. 7, 1843, reported in ' Gard. Chron ' 24 ' ' V ' 



1843, p. 86. a 



VOL. II. 



Ibid., 1862, p. 83. 



