40 On the different Species, fyc. of the Genus Brassica. 



TheColsa, the Chou-navet, and the Ruta-baga, appear from 

 these experiments to be hybrid products of the Cabbage, and 

 Turnip, taken in different degrees of culture, and domesti- 

 cation ; they are none of them capable of crossing the true 

 Cabbage, but may all become fruitful by its means ; they can 

 produce amongst themselves other cross-races which bring 

 their own seeds to perfection ; the Colsa in particular, cannot 

 be considered as the type of the cultivated Cabbage, as Messrs. 

 Duchesne and Lamarck supposed, but its manner of mixing 

 in artificial breeds, shows, as I have already observed, that it 

 forms a type sui generis. One might suppose that the Colsa 

 was originally produced from the Cabbage and the Navette ; 

 the Brassica campestris pabularia by the Cabbage and the 

 oblong Turnip ; the Napo-Brassica by the Cabbage and the 

 white Turnip, and the Ruta-baga by the Cabbage and the 

 yellow Turnip. 



GENERAL OBSERVATIONS. 



The several plants which I have offered to notice, and 

 classed according to my own observations, are, as every body 

 knows, disseminated throughout Europe ; but from the con- 

 fusion reigning in their popular and unscientific nomenclature, 

 it was impossible to know which of these species and varie- 

 ties were spoken of on different occasions, so that the experi- 

 ments of one country were useless for another, and it was im- 

 possible to deduce any general considerations on the nature 

 of these vegetables. In order to apply the classification 

 proposed I shall add two short remarks. The distinction 

 of the several varieties once established, we shall find it 



