A i 
INTRODUCTORY ESSAY. vil 
In conclusion, if I may venture to assume a limit to the Flora of New Zealand, from the data 
at my disposal, and from a comparison of these with those of better investigated countries with which 
I am familiar, I should regard 4000 as the probable approximation; of which 1000 may be flowering 
plants. Compared with any other countries in the same latitude, this is a very scanty Flora indeed, 
especially as regards flowering plants; of which Britain contains, in about the same area, upwards of 
1400 species; and in Tasmania, not yet well explored, and only containing one-third of the area, 
upwards of 1000 have already been discovered. In Cryptogamic plants, on the other hand; these 
islands are extremely rich; not only proportionately to the Phzenogamic, but absolutely so. Great 
Britain, where these lower Orders have been assiduously studied for fifty years, contains about fifty 
Ferns, and Tasmania sixty-four. 
In the above remarks I have not alluded to the Floras of some outlying islands, all of which 
have more or less claim to be considered botanically as a part of New Zealand. Of these, the extent 
of its Flora renders Norfolk Island the most important: it contains many more tropical forms than 
New Zealand, and is also more closely connected with the Pacific and Australian Floras. Chatham 
Island* has been visited by Dr. Dieffenbach, who brought thence a very few plants, all identical with 
or closely allied to New Zealand species. Lord Auckland's Group and Campbell’s Island were 
investigated by myself in the Antarctic Expedition, and also by the French and American Antarctic 
Expeditions, under Admiral D'Urville and Commodore Wilkes. All the known species have been 
published in the first volume of the ‘ Antarctic Flora; they are almost all identical with or closely 
allied to New Zealand plants, and amongst them are found a few Antarctic American ones, not 
hitherto discovered in New Zealand. They include 370 species, of which 100 are flowering plants, 
and of these again 54 are known natives of New Zealand. As however neither these islands, nor 
the mountains of the Middle Island of New Zealand, have been explored satisfactorily, it is probable 
that a much larger proportion of their flora is common to both. 
CHAPTER II. 
ON THE LIMITS OF SPECIES; THEIR DISPERSION AND VARIATION. 
Iv is no part of my present object to discuss the theoretical views that have been entertained on these 
obscure subjects: my aim is to draw attention to a few leading questions of great practical importance, 
which ought not to be overlooked, even if they do not force themselves on the notice of natu- 
ralists. In explanation of my meaning I shall assume certain positions}, and adopt them as principles 
* A few Chatham Island plants were engraved in Paris many years ago for a magnificent work, * Voyage de 
la Venus; but the letterpress of that publication has never appeared, nor has the Botany of that voyage been 
completed. 
T Ineed hardly remark that these have no claim to originality ; they are merely selected as heads of the subjects 
upon which I intend to enlarge. 
