DISTRIBUTION. ` 17 
rogion of India Deserta to the lower Western Himalayan slopes only; it is also present 
in Ceylon. D. latifolia recurs in the Andamans and the Malay Peninsula, and is 
more widely distributed under the Himalaya than D. lanceolaria ; it does not go 
to Ceylon. D. paniculata recurs in Central and Eastern Indo-China; D. volubilis üni 
throughout the Himalaya, and is equally widespread in Indo-China. 
In Coromandelia there is but one endemic species—D, coromandeliana, so that the 
endemie factor is $, or 166. Of the others, four have been mentioned in detail under 
Malabaria; the fifth (D. spinosa) is common in the Sundribuns at the head of the Day 
of Bengal, occurs on Indo-Chinese coasts, and is reported from those of the Philip- 
pines. The degree of isolation for Malabaria is low, being little above that for the 
Malay Peninsula, which does not stand apart from the rest of Malaya; that for 
Coromandelia is still lower, and the two areas must therefore be taken  conjointly. 
When thus united, the endemic factor for Peninsular India, including Ceylon and the 
Indian deserts, is only у, or 35:3—not much higher than the factors for tho 
Philippines and rather lower than that for Borneo. . 
When the Himalayan and Sub-Himalayan area is considered, we find eleven species 
with only one (D. sericea) absolutely limited to the region. The existence of D, sericea 
is not, however, the full measure of evidence that this Himalayan tract is really а 
natural area, for D. Sissoo is almost as characteristic of the region as D. sericea, since 
it is even more widespread throughout the tract and only overflows westward into the 
Indian Desert region. However, it seems hardly worth while to recognise as a subarca 
apart, for this genus, a region with an endemic factor of үү, or only 9; the question is, 
what is the most convenient and least unnatural measure to adopt? .The distribution 
of the remaining species is: D. Janccolaria, to India and Ceylon only; 2, latifolia, 
throughout India and to the Andamans and the Malay Peninsula; D, volubilis, to India 
and Indo-China equally; D. rimosa, to Western Indo-China, South-Western China, and 
Tongking ; D. confertiflora, to Western and Central Indo-China; D. stipulacea, to Western, 
Central and Eastern Indo China, and to South-Western China; D, assamica and D. 
mimosoides, to Western Indo-China and South-Western China; D. tamarindifolia, to Western 
and Central Indo-China and South-West China, passing beyond this to Malaya and the 
Philippines. Now of those species distributed eastward across the Brahmaputra, all save 
D. volubilis ave absent from India, and at the same time are confined to the Eastern 
Himalaya; while of those found both іп the Himalaya and in India, one (D. lanceolaria) 
is confined to the Western Himalaya, The best solution of the difficulty seems to 
be, therefore, to annex the western half of the Himalaya to India and the eastern half 
to Western Indo-China. This renders our India practically co-extensive with the area 
occupied by D. lanceolaria, and gives it an endemic factor of i7, or H. | | 
In Western Indo-China, between the Brahmaputra and the Irawaday, there are 17 
species, of which only two аге endemic— 2, Wattii and D. Thomsoni. The. endemic 
or 117, thus hardly exceeds that for the Himalaya. The distributed 
to South-Western China only; D. congesta, to Malabaria only ; 
South-Western China, and Tongking ; D. spinosa, 
to the coasts of Coromandel, Tenasserim, and the Г hilippines ; D. volubilis, throughout 
India, the Himalaya, anl Central In lo-China ; 2. mimosoides and Ð, assamica, to 
the Eastern Himalaya and South-Western China; D. stipulacea, D. confer tiflora, wis s 
tamarindif.lia, both to the Eastern Himalaya and to Central Indo-China, the first ` 
these occurring also in South-Western China and stern Indo-China, the last о 
the three extending {о South-Western China, the Philippines, and Malaya; D. rentformis 
9 
species are—D, Kingiana, | 
D. rimosa, to the Eastern Himalaya, 
Ann. Roy. Bor, Garp. Carcurra, Vor. A. 
