Pandit Govind Ballabh Pant Memorial Lecture: II

- Eastern Himalaya: These range from Central Bhutan and whole of Arunachal
Pradesh. Here, warm-moist conditions prevail. The tree-line is high. There is
considerable diversity in rhododendrons and there is Chinese influence like takin,
Temmink’s tragopan.
According to the studies of the Botanical Survey, India has about 17,000 flowering
plants. Out of which nearly 8,000 species grow in the Himalaya and 5000 species in
North eastern India, (Sharma B.D. 1992.personal communication). Several species
may be common to these and other parts particularly the Gangetic Plains. The
number of species growing exclusively in the Himalaya has yet to be determined.
Chatterjee (1939) made detailed studies on the endemism in the Indian flora. He
observed that Indian flora has been influenced by adjoining countries/regions like
Myanmar, Malaysia, Indonesia and even Philippines;Eastern Mediterranean; Africa,
Madagascar and Sri Lanka. Even so, according to him the number of endemics in
the Himalaya are 3165 out of a total of 6850 endemics in India. In other words,
Himalaya has a very high percentage of endemics (about 50%). Among the largest
genera in India are Impatients and Primula. The former has 189 species, about 112
of which grow in the Himalayan belt while 77 in Western Ghats. Hardly one species
is common to the two disjunct regions. Similarly, Primula has 162 species out of
which 148 are endemics (Chatterjee, 1939). Special mention may be made of some
botanical rarities of Western Himalaya: there are Blanophora involucrata (a
saprophyte) and Cyperipedium cordigerum.
Eastern Himalaya
From the point of biodiversity, North-Eastern region is very rich and harbours the
largest number of endemics and Schedule1 species than any where in the country
(MacKinnon and Mac Kinnon, 1986). For instance, one of the unique botanical rarity
of the Eastern Himalaya is Sapria himalayana. It is a parasitic species which has
been sighted only twice since 1836. The flowers are 35cm across and buds are
about the size of a grape fruit. Sahni (1982) has enumerated several of such
vanishing taxa. Unfortunately, protective measures are not commensurate with the
biological holdings of this region. This region is a meeting ground of Indo- Malayan
and Indo-Chinese biogeographical realms as well as Himalayan and Peninsular
Indian elements. In fact, as stated earlier that it is here that the peninsular plate
struck against Asain landmass, after it broke off from Gondwanaland. Therefore, it is
not surprising to find some of the primitive angiosperm families in this and
contiguous areas. These are: Magnoliaceae, Digeneriaceae, Himantandraceae,
Eupormatiacea, Winteraceae, Trochodendracea, Tetracentraceae and
Lardizalbaleaceae. Specific primitive genera are: Alnus, Aspidocarya, Betula,
Decaisnea, Euptelea, Exbucklandia, Haematocarpus, Holboellia, Houttuynia,
Magnolia, Magelietia, Pycnarrhena and Tetracentron. (Malhotra and Hajra, 1977).
Takthajan (1969) was led to believe that this region alongwith contiguous regions
is the cradle of flowering plants. The occurrence of Nepanthese khasiana,
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