310 DR. HOOKER ON THE DISTRIBUTION OF ARCTIC PLANTS. 



Observations on the Species. 



In the preceding table I have attempted to group the arctic plants under comprehen- 

 sive forms, founded on a careful study of the plants indicated by the names quoted : this 

 I first did with as little reference as possible to the labours of others,— endeavouring, as 

 far as was in my power, to suppress my preconceived ideas, whether original or adopted. 

 Having thus arrived at the nearest possible approach to independent conclusions, when I 

 compared my work with the descriptive Floras which I have elsewhere indicated as forming 

 the basis of the Systematic Catalogue, I was surprised to find how many authors have 

 directly or indirectly arrived at the same conclusions as myself with regard to the specific 

 limits of the plants indicated. In some instances such revision corrected my previous views; 

 but in by far the most numerous cases the summing up of this authoritative evidence 

 afforded extraneous reasons for abiding by my own conclusions. The following notes are 

 intended both to give these extraneous reasons, and to show to how much greater an extent 

 than is generally supposed, the most able and experienced descriptive botanists vary in 

 their estimate of the value of the " specific term" as applied to many of the commonest 

 plants of the best-known countries. Prom the results of this and other most perplexing 

 and laborious comparisons of the labours and opinions of the authors of many local and 

 general Floras, I think I may safely afiirm tliat the specific term has three different 

 standard values, all current in descriptive botany, but each more or less confined to 

 one class of observers, though more or less variable with all. With the general bota- 

 nist it is a comprehensive term, and becomes more so with age and experience ; with 

 the monographer of large and widely diffused natural orders or genera its standard 

 is cojitracted at first, but rapidly expands in successive revisions of his work; while 

 the local Ijotanist, or monographer of genera or orders Avith restricted ranges, begins 

 with a rather broad standard, which rapidly contracts. This is no question of what is 

 right or wrong as to the real volue of the specific term. I believe each is right according 

 to the standard he assumes as the specific ; moreover, in the majority of cases all agree 

 with regard to the absolute and undeniable distinctness of a moiety of the plants of every 

 area * ; all agree with regard to the permanent distinctiveness of many of the subspecies, 

 varieties, &c. of the other or variable moiety ; and all agree with regard to the propriety 

 and importance of tracing the characters and ranges of varieties as carefully as of species. 

 Still the questions remain — Should the specific term ever be arbitrary ? and if so, should 

 it be broad or narrow ? I believe it must often be arbitrarily defined, and that it shoidd be 

 broad, because the object of botanical nomenclature is defeated by an undue multiplica- 

 tion of names necessary to be borne in mind by the general botanist, whose convenience 

 ought first to be considered, and also because the multiplication of specific names will 

 demand a corresponding increase of generic ones ; moreover the daily discovery of inter- 

 mediate forms, or new or closely allied forms, is introducing an incessant change in the 

 nomenclature of narrowly defined species. 



* See Introd. Essay to Tasmanian Flora, j). v, for some ideas as to the objeetive and subjective values of the charac- 

 ters of species, and the division thereby of all species into groups. 



