120 ORIGIN OF CULTIVATED PLANTS. 



In order to understand the difficulties which it 

 presents, we must fii'st ascertain what nearly allied forms 

 authors designate — sometimes as distinct species of the 

 cjenus Linuni, and sometimes as varieties of a single 

 species. 



The first important work on this subject was by 

 Planchon, in IS-iS.^ He clearly showed the differences 

 between Liniim usitatissimurn, L. huniile, and L. angiis- 

 tifolium, which were little knoAvn. Afterwards Heer,'-^ 

 when making profound researches into ancient cultivation, 

 went again into the characters indicated, and by adding 

 the study of two intermediate forms, as well as the com- 

 parison of a great number of specimens, he arrived at the 

 conclusion that there was a single species, composed of 

 several slightly different forms. I give a translation of 

 his Latin summary of the characters, only adding a name 

 for each distinct form, in accordance with the custom of 

 botanical works. 



Linuon usitatissmiuon. 



1. Annuuin (annual). Root annual; stem single, 

 upright ; capsules 7 to 8 mm. long ; seeds 4 to 6 mm., 

 terminating in a point, a. Vidgare (common). Capsules 

 7 mm., not opening when ripe, and displaying glabrous 

 partitions. German names, Schliessletn, Dreschleva. 

 /3. Huniile (low). Capsules 8 mm., opening suddenly when 

 ripe ; the partitions hairy. Linmn hu'tnile, Miller ; L. 

 crepitans, Boninghausen. 'German names, Klanglein, 

 Springlein. 



2. Syemcde (winter). Eoot annual or biennial; stems 

 numerous, spreading at the base, and bent; capsules 

 7 mm., terminating in a point. Linv/m hyemale roma- 

 oiiioii. In German, Winterlein. 



3. Amhiguum (doubtful). Eoot annual or perennial ; 

 stems numerous, leaves acuminate ; capsules 7 mm., with 

 partitions nearly free from hairs; seeds 4 mm., ending in 

 a short point. Linuon amhiguum, Jordan. 



4. Angustifoliuin (narrow -leaved). Root annual or 



^ Planchon, in Hooker, Journal of Botany, vol. vii. p. 165. 

 ^ 'Reer, Die Pflanzen der Pfahlhaute7i,in4to, Ziivich, l86o,p. 35 ; Ueher 

 den Flachs und die Flachskidtttr, in 4to, Ziiricb, 187-. 



