302 LAWS OF VAKIATION. Chap. XXIY 



" seed, one direct from Europe, the other saved at Bangalore (of 

 " which the mean temperature is much below that of Madras), were 

 *' sown at the same time : they both vegetated equally favourably, 

 " but the former all died off a few days after they appeared above 

 " ground; the latter still survive, and are vigorous, healthy plants." 

 " So again, turnip and carrot seed saved at Hyderabad are found to 

 *' answer better at Madras than seed from Europe or from the Cape 

 '' of Good Hope." " Mr. J. Scott of the Calcutta Botanic Gardens, 

 informs me that seeds of the sweet-pea (Lathy rus odoratus) imported 

 from England produce plants, with thick, rigid stems and small 

 leaves, which rarely blossom and never yield seed ; plants raised from 

 French seed blossom sparingly, but all the flowers are sterile ; on 

 the other hand, plants raised from sweet-peas grown near Darjeeling 

 in Upper India, but originally derived from England, can be suc- 

 cessfully cultivated on the plains of India ; for they flower and seed 

 profusely, and their stems are lax and scandent. In some of the 

 foregoing cases, as Dr. Hooker has remarked to me, the greater 

 success may perhaps be attributed to the seeds having been more 

 fully ripened under a more favourable climate ; but this view can 

 hardly be extended to so many cases, including plants, which, from 

 being cultivated under a climate hotter than their native one, 

 become fitted for a still hotter climate. We may therefore safely 

 conclude that plants can to a certain extent become accustomed to 

 a climate either hotter or colder than their own ; although the latter 

 cases have been more frequently observed. 



We will now consider the means by which acclimatisation 

 may be effected, namely, through the appearance of varieties 

 having a different constitution, and through the effects of 

 habit. In regard to new varieties, there is no evidence that 

 a change in the constitution of the offspring necessarily stands 

 in any direct relation with the nature of the climate inhabited 

 by the parents. On the contrary, it is certain that hardy 

 and tender varieties of the same species appear in the same 

 country. New varieties thus spontaneously arising become 

 fitted to slightly different climates in two different ways ; 

 firstly, they may have the power, either as seedlings or when 

 full-grown, of resisting intense cold, as with the Moscow 

 pear, or of resisting intense heat, as with some kinds of 

 Pelargonium, or the flowers may withstand severe frost, as 

 with the Forelle pear. Secondly, plants may become adapted 

 to climates widely different from their own, from flowering 

 and fruiting either earlier or later in the season. In both 



^' 'Gardener's Chronicle,' 1841, p. 439. 



