Corzwso.— Botany of the North Island of New Zealand. 235 
specific distinctions really such? Has a species a power of evolution and 
metamorphosis per se; which, the factors, time, suitable soils, and ‘climate 
being given, knows no bounds? Have there been in past æras any potent 
occult elemental causes at work, differing only in intensity, combination, and 
constancy from what now are, through which sub-varieties, varieties and 
species were the more readily evolved? May not a plant be outwardly 
distinct, yet chemically the same? May a plant be almost entirely outwardly 
the same with another, and yet chemically distinct? May not nature educe, 
under the most favourable circumstances, from two genera slightly differing, 
fertile plants forming new genera more divergent? and may not such (again 
crossed by nature) produce plants still more widely differing ? Why, 
among several species of any given endemic genus (e.g. Coprosma, Dracophyl- 
lum, Veronica), should some species be of robust and vigorous growth and 
development, and common everywhere ; other species of weakly growth and 
development, and comparatively scarce ? Are some of these forms older than. 
others? and if so, which are the seniors? Are not the more robust and 
vigorous ones, through their own progressive increase, likely to extirpate 
the weaker ones? . . Such are some of the thoughts which 
must often arise in the intelligent botanist’s mind, especially when contem- 
plating new or old forms in far off insular situations. 
II. GEOGRAPHIC. ; 
3. But laying aside the ideal and theoretical, and coming to the practical 
and real, how does the vegetation of this Northern Island of New Zealand 
appear when seen for the first time? What is its peculiar aspect? The 
answer will mainly depend on two things : first, the place whence the newly- 
arrived beholder last came ; and second, the place in New Zealand where he 
lands; not forgetting his expectations—as the eye ever sees what the mind 
brings. If he last left the shores of Great Britain, then the recollection of 
her verdant fields may cause the brown fern-clad hills and dark-green forests 
of New Zealand to appear the more gloomy and sad; if his last landscapes 
were either South African or Australian, then their glaucous sea-green hue 
and arid appearance will be agreeably contrasted with New Zealand forest 
vegetation; but if he should have come hither direct from the sunny skies 
and islands of the tropies, with their graceful perennial light ever-green 
dress, then the New Zealand hills and dells may appear very sombre, and 
will suffer from recollection and comparison. Again, if he should happen to 
anchor in one of the many rivers or harbours north of the Thames, while 
the ubiquitous brown fern (Pteris esculenta) is everywhere, he will be 
struck with the appearance of the white mangrove (Avicennia officinalis) 
growing within the range of the tide, and the romantic pohutukawa (Metro- 
