a Study in Taxonomic Distribution. 
2 7 
farther from Stewart than from the Chathams. But if we draw a line direct 
from Stewart to the Chathams, and use it as the diameter of a circle, this 
circle cuts New Zealand near Lake Taupo in the North Island, and near 
Foveaux Strait. One will therefore expect to find, to a large extent, that 
those species which occur in the Chathams, and reach Lake Taupo as well 
as Foveaux Strait, will occur in Stewart, unless that island was cut off too 
early, a point as to which we have no information. 
The southern invasion, as we shall see in the next paper, probably 
passed not very far from the Aucklands, and a circle with its centre iri 
Dunedin and passing through Stewart also passes through the north end of 
South Island. One will therefore expect to find most Auckland species 
that reach the north end of South Island also occurring in Stewart, again of 
course in so far as an early cutting off of Stewart may not have interfered. 
A family will very rarely arrive in a country as a group of genera 
simultaneously ; some will arrive sooner than others. On the whole , there- 
fore, a family with several genera will be older in the country than one with 
one, and the same will be true of genera, those with many species being on 
the whole the older. Now as the Stewart flora is mainly composed of older 
forms, we shall not go far wrong if we predict that it will contain most of 
those families that contain more than the average number of genera (in 
New Zealand proper), and those genera that contain more than the average 
number of species. This then may be added to the previous predictions. 
As, however, there are not so many families and genera with numbers above 
the average, this will not, probably, add very many. 
We shall now give a complete list of the flora of Stewart, marking 
against each species and family the result of applying to it these different 
predictions. Everything that is actually predicted is printed in italics. As 
a rule when a genus or family is predicted some of the actual species are 
also predicted, but in the few cases where this does not happen, the genus 
or family is printed in italics, the species in roman type. 
Table I (and cf. p. 42). 
A occurring in the Kermadecs, Chathams, and Aucklands, or the two latter. 
B occurring in the Chathams, and reaching Lake Taupo and Foveaux Strait, 
C occurring in the Aucklands, and reaching the north end of South Island. 
Families with five or more genera, and genera with five or more spp., are marked with f» 
ABC 
ABC 
RANUNCULACEAE 
Clematis + indivisa 
Ranunculus + Lyallii 
xxx 
MAGNOLIACEAE 
Drimys colorala 
CR UCTFERA E + 
Cardamine f hinsuta 
Lepidium f oleraceum 
tenuicaule 
VIOLACEAE 
Viola filicaulis 
xxx 
xxx 
xxx 
gracilipes 
liirtus 
Kirkii (endemic St ) 
lappaceus 
rivularis 
acaulis 
x 
xxx 
x 
X 
