284 N. ANNANDALE. 



shrub ill the thickets. After it in order of numbers come Canthium parvifLorum, 

 Capparis hrevispina and Randia malaharica. With these grow numerous other plants 

 which it is hard to call definitely either shrubs or creepers, as they appear to depend 

 for support on firmer plants more at some spots than at others. Such are Zizyphus 

 oenoplia and some of the numerous forms of Premna lati folia. 



True creepers form an important element in the vegetation of the thickets. 

 They are of three kinds, woody, succulent and herbaceous. 



The woody creepers or liaiias are almost as large and as abundant as in a tropical 

 rain-forest, at any rate in those parts in which the original Banyans have disappeared ; 

 but they are deciduous. On the Banyans that remain, and indeed also on the fig- 

 trees of other kinds, these creepers find it difficult to spread themselves. Apparently 

 most of the species that are found on the island must commence their growth in fairly 

 open places and cannot start to grow upright in dense shade. It is only, therefore, 

 when they can first trail over bushes or smaller trees that they can reach the tops of 

 the figs and there luxuriate. In this way, by growing first over a small thicket of Glycos- 

 mis, Aganosma caryophyllata occasionally almost overwhelms a large fig. This is one of 

 the largest and certainly the most conspicuous liaiia on the island, but it is not very 

 common. Its masses of white sweet-smelling blossoms last from July to September or 

 October and in these months it is a most beautiful object. Far commoner is the vine 

 Vitis vitiginca, which also flowers in the rainy season. Its blossoms are much less 

 conspicuous in Ihemselves but are rendered almost as noteworthy by the flocks of 

 butterflies (especially Papilio polytes) always hovering over them. In the older parts 

 of the thickets this vine is perhaps the commonest species of liafia, but towards the 

 edge of the island Gymnema ccylonica, Combretum extensum and D alter gia monos- 

 perma, are more abundant. Derris scandens and Acacia intzia are more characteristic 

 of the Pongamia zone, but the latter creeper penetrates into the central thickets 

 towards the east end of the island. 



A characteristic feature of the lianas is that several different species often grow 

 together, with their branches intertwined, and yet each remains in a flourishing 

 condition. The masses of their foliage often appear to overwhelm the trees that 

 support them (especially Nim trees) without killing their hosts. 



The only two completely succulent creepers in the flora of Barkuda are Vitis 

 quadrang'ularis and Sarcostemma brevistigma. The former is the most generally 

 distributed creeper on the island in all types of vegetation that include shrubs or trees. 

 Its curious jointed stems hang in festoons on a very large proportion of the trees of 

 all species. It has this advantage that it can spring up and grow without incon- 

 venience in the densest shade. The fleshy leafless stems of the Sarcostemma, which 

 is much less abundant, as a rule trail over Prickly Pears in fairly open spots. 



I have already noticed that herbaceous creepers play a much less important 

 part in the vegetation of Barkuda than they do in that of high rocky headlands in 

 the vicinity. It is interesting to note that .several species common on the headlands 

 [e.g. Ipomaea sepiaria) occasionally establish a single plant on the island, without 

 ever becoming in any way common. Other creepers, common on richer soil on the 



