Journal Number 110
November 2008

Notes etc

Gordon Sylvester emailed "In 1864 J.D.Hooker wrote, under the authority of the Government of
New Zealand, a Handbook of the New Zealand Flora, "a systematic description of the Native plants
of New Zealand and the Chatham, Kermadecs, Lord Auckland's , Campbell's, and MacQuarrie's
Islands."

The introduction is more than 35 pages, titled "Outlines of Botany". The main body of text is
extensive, with the Orchid family occupying 13 pages, with 18 genera and 38 species. On reading
this part I was intrigued to note the method by which Wm. Colenso determined his collections.
It appears he may have had access to a copy of the book. Certainly, as intimated in our Historical
Series No.1, both J.D. Hooker and Wm. Colenso were known to each other at this time.*

"One part of the outlines of Botany caught my eye as still relevant today as it was when written
some 158 years ago. In Chap 4, Hooker detailed, "the collection, preservation and determination
of plants". It was the "determination of plants" that caught my eye.

'§245. To assist the student in determining or ascertaining the name of a plant belonging to
a flora, analytical tables should be prefixed to the Orders, Genera, and Species. These tables
should be so constructed as to contain, under each bracket, or equally indented, two (rarely
three or more) alternatives as nearly as possible contradictory or incompatible with each other,
each alternative referring to another bracket, or having under it another pair of alternatives
further indented. The student having a plant to determine, will first take the general table of
Natural Orders, and examining his plant at each step to see which alternative agrees with it, will
be led on to the Order to which it belongs; he will then compare it with the detailed character of
the Order given in the text. If it agrees, he will follow the same course with the table of the genera
of that Order, and again with the table of species of the genus.

But in each case, if he finds that his plant does not agree with the detailed description of the genus
or species to which he has thus been referred, he must revert to the beginning and carefully go
through every step of the investigation before he can be satisfied. A fresh examination of his
specimen, or of others of the same plant, a critical consideration of the meaning of every
expression in the characters given, may lead him to detect some minute point overlooked or
mistaken, and put him into the right way.

Species vary within limits which it is very often difficult to express in words, and it proves often
impossible, in framing these analytical tables, so to divide the genera and species, that those
which come under one alternative should absolutely exclude the others. In such doubtful cases
both alternatives must be tried before the student can come to the conclusion that his plant is
not contained in the Flora, or that it is erroneously described.

'§246. In those Floras where analytical tables are not given, the student is usually guided to the
most important or prominent characters of each genus or species, either in a general summary
prefixed to the genera of an Order or to the species of the genus, for all such genera or species:
or by a special summary immediately preceding the detailed description of each genus or species.
In the latter case this summary is called a diagnosis. Or sometimes the important characters are
only indicated by italicizing them in the detailed description.

Hooker goes onto to detail occasional or accidental anomalies peculiar to that single one, or to a
very few individuals, which may prevent the species from being at once recognised by its technical
characters. He then goes on to point out a "few" of those anomalies.

"Reading those remarks and the manner they are couched in leads me to a conclusion that
collectors can either put in too much effort in determining a species, or not put in enough.
Where to draw the line? The lumpers and the splitters will continue to plague the others'
thought processes and keep controversy to the fore. So may it continue."

* Indeed, Colenso's 100+ letters to Kew are the subject of a book we will publish next year: Colenso started sending specimens to WJ Hooker in 1840, met JD Hooker at the Bay of Islands in 1843 and corresponded with him for the next 55 years; he received a copy of the Handbook, and criticised it sharply in a letter dated 29 November 1865 - Ed.