PLANTS CULTIVATED FOR THEIK FEUITS. 301 



The species is, therefore, a native of the region lying at 

 the foot of the western mountains of the Indian Penin- 

 sula, and its cultivation in the neighbourhood is probably 

 not earlier than the Christian era. It was introduced 

 into Jamaica by Admiral Rodney in 1782, and thence 

 into San Domingo.* It has also been introduced into 

 Brazil, Mauritius, the Seychelles, and Rodriguez Island.^ 



Date-Palm — Fhcenix dactylifera, Linnaeus. 



The date-palm has existed from prehistoric times in 

 the warm dry zone, which extends from Senegal to the 

 basin of the Indus, principally between parallels 15 and 

 30. It is seen here and there further to the north, by 

 reason of exceptional circumstances and of the aim which 

 is proposed in its cultivation. For beyond the limit 

 within which the fruit ripens every year, there is a zone 

 in -which they ripen ill or seldom, and a further region 

 within which the tree can live, but without fruiting or 

 even flowering. These limits have been traced by de 

 Martins, Carl Ritter, and myself^ It is needless to repro- 

 duce them here, the aim of the present work being to 

 study questions of origin. 



As regards the date-palm, we can hardly rely on the 

 more or less proved existence of really wild indigenous 

 individuals. Dates are easily transported; the stones 

 germinate when sown in damp soil near the source of a 

 river, and even in the fissures of rocks. The inhabitants 

 of oases have planted or sown date-palms in favourable 

 localities where the species perhaps existed before man, 

 and when the traveller comes across isolated trees, at a 

 distance from dwellings, he cannot know that they did 

 not spring from stones thrown away by caravans. 

 Botanists admit a variety, sylvfstiis, that is to say wild, 

 with small and sour fruit ; but it is perhaps the result 

 of recent naturalization in an unfavourable soil. His- 

 torical and philological data are of more value here, 

 though doubtless from the antiquity of cultivation they 

 can only establish probabilities. 



' Tussao, Flore des Antilles, pi. 4. ' Baker, Fl. ofMav.rit., p. 282. 



* Martius, Gen. et Spec. Palmarvm, in fclio, vol. iii. p. 257 ; 0. Hitler, 

 Erdkunde, xiii. p. 760 ; Alph. de Candolle, G^og. Bot. Bais., p. 343. 



