ii2 CLASSIFICATION OF PLANTS. [PART 



Division, those of a Division than those of a Natural 

 Order, of a Natural Order than those of a Genus, and of 

 a Genus than of the Species which it includes. 



5. Botanists distinguish as varieties groups of indi- 

 viduals of a species which are marked in common by 

 some trivial character, subordinate in importance to the 

 characters which are used to separate species. Thus, we 

 may have white and red varieties of the same species of 

 Rose, awnless and awned varieties of the same species of 

 Wheat, &c. ; the colour of the flower of the Rose and the 

 presence or absence of an awn in Wheat being characters 

 too liable to variation to serve to separate species. 



6. The following pages are devoted to an examination 

 of representative types of most of the Natural Orders of 

 flowering plants native in Britain. 



I must here emphatically impress upon the beginner, 

 that it is useless attempting to study this portion of the 

 book without a constant reference to living specimens, 

 without which any information he may acquire from it 

 will be comparatively unavailable when tested in the field. 

 Numerous references are given to plants which show 

 peculiar departures from the several types. Specimens 

 of these ought to be procured whenever it is possible, 

 and dried for further use in the way described at page 

 269. When a preparation can be preserved without 

 pressing it between papers, as, for example, many dry 

 fruits, seeds, galls, spines, &c., it would be well to have 

 them thoroughly dried and mounted upon pieces of card, 

 labelled with the name of the plant, the Natural Order to 

 which it belongs, the particular in which it departs from 

 the Type, &c. 'Preparations of plants used for economic 

 purposes, whether domestic, medicinal, in the arts, or 

 otherwise, are always interesting, and are very useful for 

 purposes of illustration. A few of these, which may be 

 easily obtained, I have indicated ; but there are hundreds 

 not mentioned and equally accessible. It is, indeed, 

 scarcely possible to take a walk into the country, either in 

 summer or winter, without meeting with objects which 

 may help to throw light upon some question of botanical 

 interest, and which may be turned to account by a teacher 

 for the purposes of illustration. To the late Professor 

 Henslow nothing came amiss in this way, and his 



