vi PREFACE. 



many Species : and if I have made many such blunders, a part may be 

 attributable to the fact that various Genera were described amidst constant 

 interruptions, and all under pressure of official duties. 



The terminology employed is as simple as is attainable with a due regard 

 to precision of language. In the choice of terms I have followed Oliver's 

 Lessons in Elementary Botany ; usually avoiding such as are used in 

 single Orders only, or are of special signification in single Orders or 

 Genera. For modifications of the fruit the choice of terms presents great 

 difficulty ; and I have therefore very much confined myself to such as are 

 required to avoid periphrasis, as capsule, drupe, berry, utricle, follicle, 

 pod, &c. (about which there is no ambiguity), and to achene for the dry 

 indehiscent 1-seeded carpels of apocarpous fruits. For Grasses, Compositae, 

 &c., the term fruit is itself sufficiently explicit, its nature being ex- 

 plained in the Ordinal description. The term nutlet for the parts of the 

 fruit of Boraglnece and Labiates I have borrowed from Asa Gray. 



The Keys to the Genera are naturally arranged, but in Umbclliferce 

 I have added an artificial key, as being useful for the determination of a 

 Genus before the whole Order has been studied. I have given no keys 

 to the Species, preferring curt diagnoses which embrace the more im- 

 portant characters of the plant ; finding, moreover, from experience, that 

 such keys promote very superficial habits among students. 



For the areas and elevations inhabited by the plants of the British Isles 

 I am mainly indebted to Mr. "Watson's admirable works. The areas 

 occupied more or less continuously by the Species are here defined by the 

 counties, which thus indicate their limits. Where the words " northwards " 

 and " southwards " are used it implies that the plant ranges to Shetland in 

 the former case, and to both Cornwall and Kent in the latter. In this 

 Edition I have in all cases mentioned Ireland when the Species inhabits 

 ;that country ; and when rare or local in Ireland, its limits are taken from 

 the Cybele Hibernica of More and Moore, a standard work. I have in 

 like manner definitely ^mentioned the Channel Islands. I have ,been 

 urged by very competent botanists to include the Faroe Islands, as really 

 more British geographically than are the Channel Islands ; but, if I did 

 so, Iceland should also be included, and on the whole I have thought it 



