Chap. XIIl. REVERSION. 7 



acquired the dark colour, the thick bristles, and great tusks of the 

 -wild boar; and the young have reacquired longitudinal stripes. 

 But even in the case of the pig, Roulin describes the half-wild 

 animals in different parts of South America as differing in several 

 respects. In Louisiana the pig 12 has run wild, and is said to differ 

 a little in form, and much in colour, from the domestic animal, yet 

 does not closely resemble the wild boar of Europe. "With pigeons 

 and fowls, 13 it is not known what variety was first turned out, nor 

 what character the feral birds have assumed. The guinea-fowl in 

 the West Indies, when feral, seems to vary more than in the 

 domesticated state. 



W T ith respect to plants run wild, Dr. Hooker 14 has strongly 

 insisted on what slight evidence the common belief in their 

 reversion to a primitive state rests. Godron 15 describes wild 

 turnips, carrots, and celery; but these plants in their cultivated 

 state hardly differ from their wild prototypes, except in the succu- 

 lency and enlargement of certain parts, — characters which would 

 certainly be lost by plants growing in poor soil and struggling with 

 other plants. No cultivated plant has run wild on so enormous 

 a scale as the cardoon (Cynara cardunculus) in La Plata. Every 

 botanist who has seen it growing there, in vast beds, as high as 

 a horse's back, has been struck with its peculiar appearance ; but 

 whether it differs in any important point from the cultivated 

 Spanish form, which is said not to be prickly like its American 

 descendant, or whether it differs from the wild Mediterranean 

 species, which is said not to be social (though this may be due 

 merely to the nature of the conditions), I do not know. 



Beversion to Characters derived from a Cross, in the case of 

 Sub-varieties, Races, and Species. — When an individual having 

 some recognisable peculiarity unites with another of the same 

 sub-variety, not having the peculiarity in question, it often 

 reappears in the descendants after an interval of several gene- 

 rations. Every one must have noticed, or heard from old 

 people of children closely resembling in appearance or mental 

 disposition, or in so small and complex a character as expres- 



12 Dureau de la Malle, in ' Comptes appear to me worth copying : but I now 

 Rendus,' torn, xli., 1855, p. 807. find that Dureau de la Malle (' Comp- 

 Frorathe statements above given, the tes Rendus,' torn, xli., 1855, p. 690) 

 author roneludes that the wild pigs advances this as a good instance of 

 of Louisiana are not descended from reversion to the primitive stock, and as 

 the European Sus scrofa. confirmatory of a still more vague 



13 Capt. W. Allen, in his ' Expe- statement in classical times by Varro. 

 dit^on to the Niger,' states that fowls u ' Flora of Australia,' 1859, In- 

 have run wild on the island of Anno- troduct., p. ix. 



bon, and have become modified in ls ' De l'Espece,' torn. ii. :f>. 54, 



form and voice. The account is so 58, 60. 

 meagre and vague that it did not 



