Chap. X. ORANGE GROUP. 355 



all belong to one species ;" they ore, as he adds, nearly as numerous 

 as those of the silkworm. 



The Orange Group. — We here meet with great confusion in the 

 specific distinction and parentage of the several kinds. Gallesio, 11 

 who almost devoted his life-time to the subject, considers that there 

 are four species, namely, sweet and bitter oranges, lemons, and 

 citrons, each of which has given rise to whole groups of varieties, 

 monsters, and supposed hybrids. One high authority 12 believes 

 that these four reputed species are all varieties of the wild Citrus 

 medica, but that the shaddock (Citrus decumana), which is not known 

 in a, wild state, is a distinct species ; though its distinctness is 

 doubted by another writer " of great authority on such matters," 

 namely, Dr. Buchanan Hamilton. Alph. De Candolle, 13 on the 

 other hand — and there cannot be a more capable judge — advances 

 what he considers sufficient evidence of the orange (he doubts 

 whether the bitter and sweet kinds are specifically distinct), the 

 lemon, and citron, having been found wild, and consequently that 

 they are distinct. He mentions two other forms cultivated in Japan 

 and Java, which he ranks undoubted species ; he speaks rather 

 more doubtfully about the shaddock, which varies much, and has 

 not been found wild ; and finally he considers some forms, such as 

 Adam's apple and the bergamotte, as probably hybrids. 



I have briefly abstracted these opinions for the sake of showing 

 those who have never attended to such subjects, how perplexing 

 they are. It would, therefore, be useless for my purpose to give a 

 sketch of the conspicuous differences between the several forms. 

 Besides the ever- recurrent difficulty of determining whether forms 

 found wild are truly aboriginal or are escaped seedlings, many of 

 the forms, which must be ranked as varieties, transmit their 

 characters almost perfectly by seed. Sweet and bitter oranges 

 differ in no important respect except in the flavour of their fruit, 

 but Gallesio u is most emphatic that both kinds can be propagated 

 by seed with absolute certainty. Consequently, in accordance with 

 his simple rule, he classes them as distinct species; as he does 

 sweet and bitter almonds, the peach and nectarine, &c. He admits, 

 however, that the soft-shelled pine-tree produces not only soft- 

 shelled but some hard-shelled seedlings, so that a little greater 

 force in the power of inheritance would, according to this rule, 

 raise a soft-shelled pine-tree into the dignity of an aboriginally 

 created species. The positive assertion made by Macfayden 15 that 



n 'Traite du Citrus,' 1811. 12 Mr. Bentham, < Review of Dr. A. 



1 Teoria della Riproduzione Vegetale,' Targioni-Tozzetti, ' Journal of Hort. 



1816. I quote chiefly from this Soc.,' vol. ix. p. 133. 



second work. In 1839 Gallesio pub- 13 ' Geograph. Bot.,' p. 863. 



lished in folio ' Gli Agrumi dei Giard. 14 ' Teoria della Riproduzione,' pp. 



Bot. di Firenze,' in which he gives a 52-57. 



curious diagram of the supposed 15 Hooker's ' Bot. Misc.,' vol. i. p. 



relationship of* all the forms. 302; vol. ii. p 111. 



