PLANT NAMES 17 



species, and B. botrytis or broccoli, B. cauliflora or 

 cauliflower, B. ftmbriata or borecole, B. napus or 

 rape, are varieties under it. Others make Brassica 

 the species and B. oleracea a variety with the others. 



Then a group of species which possess in common 

 certain features of a more general nature is called 

 a genus, and in the same way genera are grouped 

 into families and families into orders. Thus the 

 Oaks, Chestnuts, and Beeches, which agree in having 

 their flowers in tassel-like clusters and their seeds 

 in the form of one-seeded nuts, make up the Beech 

 family, or FagacecB or Cupuliferce. So, too, the 

 Birches, or family of Betulacece, which have some 

 important features in common with the FagacecB, 

 are by some botanists grouped with them under the 

 order Fagales. And the plants, like Cabbage, whose 

 flowers consist of four petals like a cross, belong to 

 the family of Cruciferce. 



Linnaeus' principle, then, was to give each plant 

 two names, defining its genus and its species. This 

 is called the binomial system. We often find 

 plants described by three names. The third defines 

 the variety. The Sweet William, for example, is 

 Dianthus barbatus, but we find in seedsmen's lists 

 a number of varieties, such as Carmine Beauty, 

 Diadem, or Giant White. These are not usually of 

 any botanical importance. The modern tendency 

 is to divide and again subdivide, and so we find a 

 Fern which rejoices in the name Athyrium Filix- 

 femina angustatum congestum ramulosum. It might 

 be a member of the Royal Family ! But only the 



