PLANTS CULTIVATED FOR THEIR SEEDS. 321 



Caspian, the other in the north of Africa. This kind of 

 area, which I have called disjunctive, and to which I 

 formerly paid a good deal of attention,^ is rare in dicoty- 

 ledons, but there are examples in those very countries 

 of which I have just spoken.^ It is probable that the 

 area of the bean has long been in process of diminution 

 and of extinction. The nature of the plant is in favour 

 of this hypothesis, for its seed has no means of dispersing 

 itself, and rodents or other animals can easily make prey 

 of it. Its area in Western Asia was probably less limited 

 at one time, and that in Africa in Pliny's day was more 

 or less extensive. The struggle for existence which was 

 going against this plant, as against maize, would have 

 gradually isolated it and caused it to disappear, if man 

 had not saved it by cultivation. 



The plant which most nearly resembles the bean is 

 Vicia narbonensis. Authors who do not admit the genus 

 Faba, of which the characters are not very distinct from 

 those of Vicia, place these two species in the same section. 

 Now, Vicia narbonensis is wild in the Mediterranean 

 basin and in the East as far as the Caucasus, in the 

 north of Persia, and in Mesopotamia.^ Its area is con- 

 tinuous, but this renders the hypothesis I mentioned 

 above probable by analogy. 



Lentil Ervum lens, Linnaeus ; Lens esculenta, Moench. 



The plants which most nearly resemble the lentil are 

 classed by authors now in the genus ErvuTn, now in a 

 distinct genus Lens, and sometimes in the genus Cicer ; 

 but the species of these ill-defined groups all belong 

 to the Mediterranean basin or to Western Asia. This 

 throws some light on the origin of the cultivated plant. 

 Unfortunately, the lentil is no longer to be found in a 

 Avild state, at least with certainty. The floras of the 

 south of Europe, of Northern Africa, of the East, and of 

 India always mention it as cultivated, or as growing in 

 fields after or with other cultivated species. A botanist^ 



^ A. de Candolle, Geogr. Bot. Rais., chap. x. 



* Rhododendron ponticum now exists only in Asia Minor and in the 

 south of the Spanish ] eninsila. 



' Boissier, Fl. Orient., ii. p. 577. 



* C. A. Meyer, Verzeichniss Fl. Caucas,, p. 147. 



