xxxvm FLORA OF NEW ZEALAND. 



Europe*, and those highly sportive ; and in the Himalaya, the head-quarters of the genus, there are 

 still more species, and those (comparatively speaking) by no means variable. Again, Clematis, 

 Ranunculus, Epilobium, Apium, Lobelia, Wahlenbergia, Gaultheria, Olea, Gentiana, Calystegia, 

 Euphrasia, Luzula, and Poa, all very cosmopolitan, are as variable in New Zealand as elsewhere, 

 and some of them more so ; but as they are not as equally represented in number of species in New 

 Zealand as elsewhere, the results presented by each genus are of very different value. Thus Lobelia 

 and Wahlenbergia, though very large genera indeed in many parts of the globe where the species 

 are not conspicuously protean, are represented in New Zealand by two widely diffused and excep- 

 tionally protean species. Potamogeton and Poa (with many others) belong to a class equally common 

 in New Zealand and elsewhere, and equally variable everywhere. Epilobium, Veronica, Senecio, 

 and others, bear a larger proportion to the New Zealand Flora than to any other Flora of equal area 

 and number of species, and are decidedly as variable in New Zealand as anywhere. 



(c.) If we turn to the sparingly diffused and endemic genera, the same want of any recognizable 

 relations between extent of geographical distribution, number of species, and their variation, prevails, 

 rendering vain any attempt to characterize them by such general terms as shall convey a more ac- 

 curate or definite idea, than, that in whatever light we regard them they are all very variable ; the 

 absolutely local and well-marked genera, as Alseuosmia, Hoheria, and Carmichcelia, being quite as 

 much as or more so than the others. This leads to the last remark. 



(d.) Are the New Zealand plants more variable than those of other countries ? This it is almost 

 impossible to answer, except by giving the general impressions (and such are but too often fallacious) 

 received during my examinations; and may, I conceive, be better put thus — Have I had compara- 

 tively more difficulty in working out New Zealand plants than those of other countries to whose 

 floras I have paid equal attention ? I here again find almost insuperable obstacles to a direct an- 

 swer. If I have met with fewer difficulties in other floras, as in those of Tasmania, Europe, and the 

 Antarctic regions, it may be because my materials were better, and more assistance was available 

 from my predecessors, and not because the species were less variable ; again, if I have met with un- 

 usual difficulties in the New Zealand Flora, it is certainly in a great measure to be accounted for by 

 the very great natural obstacles in the way of a right understanding of the Natural Orders, genera, 

 and species, some of which I have mentioned at p. xxvii. Upon the whole, I do think that the 

 New Zealand genera are in proportion to their numbers more variable than those of other countries 

 whose botany I have investigated, whether insular or continental ; but I do not wish to express this 

 opinion so decidedly as to warrant any conclusion being drawn frorn it. 



In the British Flora I fiud fully seventy widely distributed genera, (out of about 512) containing 

 species as variable proportionally as any in New Zealand, besides many others containing but one or 

 two very sportive species. 



In Tasmania and Australia some of the largest genera (as Eucalyptus) are the most protean in 

 every point of view, the older individuals of each species not only differing widely from the younger, 

 but also from each other in stature, habit, and botanical characters. In Acacia, on the other hand, 

 while the young states of many individual species differ from the old as much as in Eucalyptus, the 

 latter are easily limited by constant characters in most important organs. In a third immense 

 endemic Australian genus, Banksia, the species are very local, and constant as to form ; whilst in a 

 fourth equally large and almost equally local genus of the same order, Persoonia, the species vary 



* Except, indeed, we admit with many excellent botanists, and perhaps with all our best ones, that the ma- 

 jority of the European species are reducible to a very few. 



