278 



DEFINITE ACTION OF THE 



Chap. XXIII. 



long as plants are grown in certain soils, of which Sageret 27 gives from his 

 own experience some instances. Odart, who insists strongly on the per- 

 manence of the varieties of the grape, admits 2S that some varieties, when 

 grown under a different climate or treated differently, vary in an extremely 

 slight degree, as in the tint of the frnit and in the period of ripening 

 Some authors have denied that grafting causes even the slightest difference 

 in the scion; but there is sufficient evidence that the fruit is sometimes 

 slightly affected in size and flavour, the leaves in duration, and the flowers 

 in appearance. 29 



With animals there can be no doubt, from the facts given in the first 

 chapter, that European dogs deteriorate in India, not only in their instincts 

 but in structure ; but the changes which they undergo are of such a 

 nature, that they may be partly due to reversion to a primitive form 

 as in the case of feral animals. In parts of India the turkey becomes 

 reduced in size, " with the pendulous appendage over the beak enormously 

 developed." ^ "We have seen how soon the wild duck, when domesticated 

 loses its true character, from the effects of abundant or changed food, or 

 from taking little exercise. From the direct action of a humid climate 



Islands. 



pasture 



rapidly decreases in size in the Falkland 



hi 



be the case to a certain extent with sheep in Australia. 



West 



Indies a great change is produced in the fleece of sheep, in about three 

 generations. Dr. Falconer states 31 that the Thibet mastiff and goat, when 

 brought down from the Himalaya to Kashmir, lose their fine wool. At 

 Angora not only goats, but shepherd-dogs and cats, have fine fleecy hair, 



and Mr. A ins worth 32 attributes the thickness of the fleece to the severe 

 winters, and its silky lustre to the hot summers. Burnes states positively 33 

 that the Karakool sheep lose their peculiar black curled fleeces when 

 removed into any other country. Even within the limits of England, 

 I have been assured that with two breeds of sheep the wool was slightly 

 changed by the flocks being pastured in different localities. 34 It has been 

 asserted on good authority 35 that horses kept during several years in the 

 deep coal-mines of Belgium become covered with velvety hair, almost like 

 that on the mole. These cases probably stand in close relation to the 

 natural change of coat in winter and summer. Naked varieties of several 

 domestic animals have occasionally appeared ; but there is no reason to 



2 7 ' Pom. Phys.,' p. 136. 



28 ' Ampclographie,' 1849, p. 19. 



29 Gartner, ' Bastarderz.,' s. 606, has 

 collected nearly all recorded 

 Andrew Knight (in ' Transact. Hort. 

 Soc.,' vol. ii. p. 160) goes so far as to 

 maintain that few varieties are abso- 



facts. 



31 ' Natural History Review,' 1SG2, 

 p. 113. 



32 'Journal of Eoy. Geographical 



Soc.,' vol. ix., 1839, p. 275. 



33 ' Travels in Bokhara,' vol. iii. p- 

 151. 



34 See also, on the influence of marshy 



lutely permanent in character when pastures on the wool, Godron/L'Espcce,' 

 propagated by buds or grafts. torn. ii. p. 22. 



30 Mr. Blyth, in 'Annals and Mag. of 35 Isidore Geoffrey St. Hilaire, ' Hist. 



Nat. Hist.,' vol. xx., 1847, p. 391. 



Nat. Gen.,' torn. iii. p. 438. 



