Notice of Dr. Hooker’s Flora of New Zealand. 243 
New Zealand, of which 1000 may be Flowering plants. ‘“Com- 
pared 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, upward of 1,40 
species ; and in Tasmania, not yet well explored, and containing 
only one-third of the area, upwards of 10U0 have already been 
discovered. In Cryptogamous plants, on the other hand, these 
islands are extremely rich, not only proportionately to the 
Phenogamic, but absolutely so. Great Britain, where the lower 
orders have been assidously studied for fifty years, contains about 
50 Ferns, and Tasmania 64 ;” while Dr. Hooker’s list of New Zea- 
land Ferns (including Lycopodiaces), after reducing almost half 
as many nominal species to more varieties, contains upwards of 
114 species. The same result would appear all the more striking- 
ly ona comparison with any equivalent continental tract in the 
northern hemisphere. In all British America and Oregon only 
62 species of Ferns and Lycopodiacee are recorded. ea. 
Dr. Hooker’s second chapter, on the limits of species, their dis- 
persion and variation, deals with matters of higher general interest. 
To bring the points in question fairly into view, he assumes four 
positions as heads of the subjects upon Which he proceeds to dis- 
course, namely : ; 
“1. That all the individuals of a species (as I shall ettempt to 
confine the term) have proceeded from one parent (or pair), and 
that they retain their distinctive (specific) characters. 
2. That species vary more than is generally admitted to be the 
case, 2 a 
' 3. That they are also much more widely distributed than is 
usually supposed. 
. That their distribution has been effected by natural causes ; 
but that these are not necessarily the same as those to which they 
are now exposed.” ; sis ; 
The first of these propositions should have been divided into 
two :—inasmuch as the first clause is not only open to some very 
Specious if not cogent objections which donot apply to the others, 
but is from. its very nature incapable of being supported by the 
kind of evidence which may sustain the other propositions. The 
act that we constantly see like individuals reproduced, and under 
favorable circumstances increased, from a parent stock, lays, 
Indeed, a solid ground for the inference that this process has been 
8oing on from the beginning: but how things go on, and how 
they began, are two different questions ; and it is seldom, if ever, 
that the facts and deductions which account for the former, can 
be made to throw much direct light on the latter. Why is it not 
antecedently just as probable that several or many individuals of 
fach species of plant, as identically like each other as are the 
spring to the parent now, were created at the beginning, as 
