Chap. X TREEK. 385 



variable than trees growing in their native forests, there can hardly 

 be a doubt that they have yielded a greater number of strongly- 

 marked and singular variations of structure. 



In manner of growth, we have weeping or pendulous varieties 

 of the willow, ash, elm, oak, and yew, and other trees ; and this 

 weeping habit is sometimes inherited, though in a singularly 

 capricious manner. In the Lombardy poplar, and in certain 

 fastigiate or pyramidal varieties of thoi'us, junipers, oaks, &c., we 

 have an opposite kind of growth. The Hessian oak,'" which is 

 famous from its fastigiate habit and size, bears hardly any resem- 

 blance in general aj^pearauce to a common oak ; " its acorns are 

 not sure to produce plants of the same habit ; some, however, turn 

 out the same as the parent-tree." Another fastigiate oak is said 

 to have been found wild in the Pyrenees, and this is a surprising 

 circumstance; it generally comes so true by seed, that De Candolle 

 considered it as specifically distinct.'** The fastigiate Juniper 

 {J. sutcica) likewise transmits its character by seed."^ Dr. Falconer 

 informs me that in the Botanic Gardens at Calcutta the great heat 

 caused apple-trees to become fastigiate ; and we thus see the same 

 result following from the effects of chmate and from some unknown 



cause.''" 



In foliage we ha v'e variegated leaves which are often inherited ; 

 dark purple or red leaves, as in the hazel, barberry, and beech, 

 the colour in these two latter trees being sometimes strongly and 

 sometimes weakly inherited ; '-^^ deeply-cut leaves ; and leaves 

 covered with prickles, as in the variety of the holly well called 

 ftrox, which is said to reproduce itself by seed."^ In fact, nearly 

 all the iDeculiar varieties evince a tendency, more or less strongly 

 marked, to reproduce themselves by seed.'''^ This is to a certain 

 extent the case, according to Bosc,'^* with three varieties of the 

 elm, nacely, the broad-leafed, lime-leafed, and twisted elm, in which 

 latter the fibres of the wood are twisted. Even with the hetero- 

 phyllous hornbeam (^Carpinus betulns), which bears on each twig- 

 leaves of two shapes, " several plants raised from seed all retained 

 " the same peculiarity." '°^ I ^vill add only one other remarkable 

 case of variation in foliage, namely, the occurrence of two sub- 

 varieties of the ash with simple instead of pinnated leaves, and 



"' 'Gardener's Chron.,' 1842, p. graph. Bot.,' p. 1083. Verlot, ' Sur 



36. la Production des Varie'te's,' 1865 ; p. 



'^* Loudon's ' Arboretum et Fruti- 55 for the Barberry, 



cetum,' vol. iii. p. 1731. '^- Loudon's 'Arooreium et fruti- 



'« Ibid.,' vol. iv. p. 2489. cetum,' vol. ii. p. 508. 



'" Godron (' De I'Espfece,' torn. ii. '^^ Vevlot, ' Des Varietes,' 1865, 



p. V)l) describes four varieties of Ro- p. 92. 



binia remarkable from their manner '*■• Loudon's ' Arboretum et iTuti- 



of growth. cetum,' vol. iii. p. 1376. 



'^' 'Journal of a Horticultural '^^ 'Gardener's Chronicle,' 1841, 



Tour, by Caledonian Hort. Soc.,' 1823, p. 687. 

 p. 107. Alph. De Candolle, ' Gco- 



VOL. 1. 2 c 



