W. Travers.— Hybridization of Plants. 31 
Arr. IIL—O» Hybridization, with reference to Variation in Plants. 
W. T. L. Travers, FELS 
[ Read before the Wellington Philosophical Society, 284 July, 1868.] 
Amonest the plants indigenous to the Middle Island of New Zealand, there 
are none which range more widely, both in altitude and in latitude, nor 
which present a greater amount of variation, than the Veronicas. Indeed, 
as Dr. Hooker remarks,in the notes to the Conspectus of this genus, pub- 
lished in his * Handbook of the New Zealand Flora," so numerous are the 
intermediate forms between very distinct looking species, as to render the 
species excessively difficult of discrimination, and to compel the adoption, 
for the purposes of an interim classification, of purely arbitrary characters 
founded on “ prominent prevalent differences only." Dr. Hooker, in a com- 
munication to myself in reference to a large and varied collection of speci- 
mens which I forwarded to him in the early part of 1864, whilst he was 
engaged in compiling the “ Handbook,” remarked on the possibility that the 
variation referred to might be due to natural hybridization, and asked me 
whether I thought this was the case. In reply, I expressed an opinion 
against the supposition, and the following paper contains the substance of 
the grounds urged by me against it. 
Before, however, entering upon the special question under discussion, I 
will venture to call attention to the two principal theories now prevalent 
respecting the origin of the various species of organic life found within 
particular areas. The first is, that the surface of the globe, at an early 
period, became divided into a number of great areas of population, each of 
which contained a distinct fauna and flora, distinguishable by characteristics 
proper to that particular area only; and that the various species now found 
within it have from time to time been since created in order to supply the 
place of representative species which have died out. The second is, that 
every group of organisms has a purely derivative origin, and that each exist- 
ing species is but the modified descendant, preserved by means of natural 
selection, of some other species: whilst, probably, in most cases so great a 
divergence has taken place from the original type, as to transgress the con- 
ventional circle which we draw round generic type, and induce us to refer it 
to some other genus than that to which it would originally have been assigned. | 
It has been well observed that if the first of these theories be true, all 
attempts to trace the origin of present and past faunas and floras must 
necessarily be futile, for their origin would be sufficiently elucidated in the 
. dogma that * they were created on the spot," and that such a theory would 
render paleontology a useless study, and reduce it to a mere leviathan cata- 
logue of fossils. Notwithstanding, therefore, the “ weighty difficulties which 
surround the theory of natural selection,” (as observed by the great ex- 
