THE NATURAL SYSTEM. 259 



not netted, but lie in parallel layers, and are easily 

 torn into strips, as the leaves of the flags, lily, 

 tulip, &c. 



These classes are again subdivided according to 

 their floral coverings. Class I. is divided into four 

 divisions : 



1. Thalamiflorce, in which the flowers have separate 

 petals, which, with the stamens, are not attached to 

 the receptacle or thalamus. There are twenty-two 

 British orders or families in this division. 



The name of the family is derived either from some 

 well-known species, or from some peculiar feature by 

 which it is characterized. In the former case, the 

 termination acecs is added in the Latin, and aceom in 

 English, signifying like: thus, Rosacece, rosaceous, 

 from Rosa, rose, rose-like family. In the latter case, 

 a term is used to indicate the family characteristic 

 Cruciferae, cruciferous, or cross-bearing family, from 

 the shape of the petals ; Umbellifera, umbelliferous, 

 umbel-bearing family. 



1. The Eanunculus family . . . Ranunculacea. 



2. The Berberry family Berleridacece. 



3. The Water-lily family .... Nymphceaceae. 



4. The Poppy family Papaveracece. 



17 -2 



