42 IV 1 1 /is. — The Flora of Stewart Island (New Zealand): 
the area would increase 
i 4 9 I( 5 25 36 49 
or, in other words, in equal times the increase in area occupied would be 
3 5 7 9 n 13 
so that it becomes quite easily possible for a species to spread over an 
enormous area once that its area occupied is large. Biologists who are not 
accustomed to working with figures are apt to forget that the area of 
a circle increases with the square of its diameter. 
Appendix. 
Since the above was in type, I have received from Dr. L. Cockayne, 
F.R.S., a most valuable letter of suggestion and criticism, and my one 
regret is that there is not time to think it over and incorporate the results 
in this paper, though I hope that further papers on New Zealand, which 
I have in preparation, will show its effects. 
I had originally intended to base my statements in this paper solely 
on the work of Cheeseman (1, 2), but Dr. Cockayne has called my attention 
to the fact that his report on Stewart Island (ic) contains many additions 
to the flora. There are so many that it would be unpardonable to ignore 
it, though its incorporation really makes no difference to my final results, 
and does not affect in any way the correctness of the predictions here made. 
The additions to the flora made in the paper referred to are : — 
A B 
R A NUNC ULACEAR 
Ranunculus f Crosbyi (endemic) 
Caltlia novaezealandiae 
VIOLACEAE 
Plymenanthera + dentata 
CAR YOPHYLLAC.EAE 
Colobanthus f Billardieri? 
HYPERICACEAE 
Hypericum japonicum 
MALVACEAE 
■ Plagianthus divaricatus 
TILIACEAE 
Aristotelia Colensoi 
COR I A RI A CEAE 
Coriaria thymifolia 
ROSA CEAE 
Potentilla anserina 
Acaena + novaezealandiae 
HA L OR HA GIA CEA E 
Myriophylliwi Votschii 
Gzmnera^ prorepens 
arenaria ? 
ONAGRACEAE 
Epilobium f pallidiflorutn 
junceum 
pictum 
insulare 
novaezealandiae 
C 
F1COIDEAE 
Mesejnbryanthemum azistrale 
UMBELLIFERAE + 
Azorella f Cockaynei (endemic) 
Oreomyrrhis andicola 
Ligusticzim f aromaticum 
x ARALIACEAE\ 
Panax\ anomalum 
RUBIACEAE _ 
Coprosma f rotundifolia 
areolata 
ramulosa 
retusa 
COMPOSITAE + 
Olearia f divaricata (endemic) ] 
virgata 
Celmisia f rigida (endemic) 
x Gnaphalium f trinerve 
x Raoulia f australis 
glabra 
Helichrysum f Loganii ? 
• grand iceps 
Abrotanella f linearis 
Erechtites f quadridentata 
x Taraxacum glabralmn 
S TYLIDIA CEA E 
Phyllachne clavigera 
x CAMPANULA CEA E + 
Wahlenbergia gracilis 
ABC 
x 
x 
X 
X 
X 
