214 Macteay Memoriat Vouume. 
The fragmental nature of the flora is indicated by the low ratio of the species to 
the genera; thus there are 90 species belonging to 76 genera, or 1°25 species to a 
genus ; the genera with more than one species are :—ytostemon, 2; Euphorbia, 3 ; 
Peperomia, 4; Meryta, 2; Coprosma, 2; Olea, 2; [pomea, 3; Alsophila, 2; Pteris, 
2; and Polypodium, 2. 
The community of species between Norfolk Island and Lord Howe Island is 34 
out of 90, or 40 per cent.—certainly not large, but if we eliminate the endemic 
species, of which there are only five in common, then the community is about 60 per 
cent. 
ITX.—Species or Piants 1x Lorp Howe Istanp. 
The total recorded species is 207, belonging to 154 genera, or about 1°34 species 
to a genus—very little in excess of the ratio for Norfolk Island. The number of 
species peculiar and non-Australian is 65, or 31°4 per cent., being nearly one-half less 
than the proportion for Norfolk Island. The affinity of the species is certainly 
greater with Australia than with any other region of the Australasian Province ; 
and if we were to disregard the neighbouring floras, then that of Lord Howe Island 
might be accepted as part of eastern continental Australia. But as the flora presents 
certain marked affinities with that of New Zealand, and keeping in mind the large 
community of species between Norfolk Island and Lord Howe Island, and the fairly 
well marked affinity generically with Norfolk Island and New Zealand, there is no 
choice but to regard Lord Howe Island as a companion outlier to Norfolk Island of 
the New Zealand region. 
It cannot have escaped notice that there is a general absence in the Lord Howe 
Island flora of the characteristic Australian types, and that there is no indication in 
the relationship of the flora to that of Papua of a land-connection between these two 
islands, as has been suggested because of the comparative shallow soundings which 
connect one with the other and Lord Howe Island with New Zealand. Unfortu- 
nately the geology of Lord Howe and Norfolk Islands does not help us to solve the 
problem of the date of the isolation of these insular masses, though Professor David 
has ventured the opinion that the voleanic material, which is the subterstructure of 
Lord Howe Island, is probably of not older date than Tertiary. The antiquity of 
the land-surface of Lord Howe Island would permit of the reception of Australian 
immigrants, since its severance from an extended New Zealand area, in greater numbers 
than would be possible to the more distant Norfolk Island ; though in earlier times 
it may have also been a line of intercommunication between continental Australia and 
what is now New Zealand. 
