( « ) 
sliows us that the greatest part of these resemblances occurs among herbaceous 
species. The study of so-called cosmopolitan plants, however, appears to me 
not less important. If it is true that those plants which have the widest 
range over our globe are at the same time those which have survived the 
greatest number of geological changes, then I am inclined to consider water 
plants as the most ancient. The similarity, nay identity, of a great proportion 
of aquatic plants in the most remote and elimatogically different countries 
now unconnected with each other, makes such an assumption not improbable. 
The aquatic types, which are more or less developed in so many families, 
deserve particular notice in our inquiries into the laws of distribution of plants. 
Returning now from the scientific classification and distribution to com¬ 
pare the general growth of the plants and their habit, we obtain the following 
result 
Description. 
Dicotyledons. 
Monocotyledons. 
Species. 
Proportion to the 
whole flora. 
Number. 
Proportion to the 
whole flora. 
Trees, large and small ... 
194 
1:26 
15 
1:48 
Shrubs 
116 
1: 44 
... 
C«s * 0 0 
Climbers 
64 
1:81 
18 
1:29 
Perennial plants 
92 
1: 56 
69 
1:75 
Annuals and Biennials 
21 
1:247 
1 
1:520 
The proportion of woody plants to herbaceous ones is, therefore, for the 
Dicotyledons 3’5 : 1; for the Monocotyledons 1: 11*4; and for the whole flora, 
3*9: 1 (by including, however, the naturalized plants, it is much altered, 
namely, nearly 2*3 :1). 
The following is a comparative table of the proportion of the woody 
plants in several insular floras to the herbaceous :— 
Galopagos ... 
... 1 : 60-6 
Iceland 
... 1 : 20-2 
Ischia 
... 1 : 11-0 
Aden 
... I : TO 
Hong-Kong ... 
... 1 : 2-0 
Singapore 
... T7 : 1 (including naturalized plants= 
1-57 : 1). 
Andamans ... 
... 3-9: 1 ( ,, „ „ = 
2-3 : 1). 
The Andamanese flora, arranged according to the habitats of the different 
species, will show the following rough results 
Marine plants 
Mangrove and salt marshes 
Sandy beaches 
Forests 
Woodless spots and cultivated lands (indigenous) 
1 
29 
53 
418 
19 
It would be interesting also to compare the floras of the eastern and 
western coasts with the corresponding ones of the neighbouring continent 
and islets. But this I am unable to perform from w r ant of sufficient data. 
A similar peculiarity as on the Galopagos Archipelago, viz., the restriction 
of peculiar forms to the different islands, appears to me, will probably exist, as 
I met with several facts bearing on this subject as a species of Corypha on 
Termoldee Island, a Phoenix on Cinque Islands, Tacca pinnatijida on Crab 
Island, Pogonatherum saccharoideum on Barren Island, &c. 
28. It is a difficult matter to say anything about the proportion of 
Proportion of the Cryptogams to the cryptogamm to the phanerogams from the 
the Phanerogams. material collected in so short an exploration. 
7 
