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XXIX. Descriptions of Indian Gentianez. By Davin Don, Esq., Libr. L.S., 
$ Prof. Bot. King’s Coll. Lond. 
Read November 3rd and 17th, 1835. 
AMONG the numerous families which compose the class of Dicotyledonous 
plants there is, perhaps, none so equally and generally distributed over the 
surface of the globe as the Gentianec, for they are found dispersed throughout 
the greater part of both hemispheres; and this observation applies not to the 
entire family only, but likewise to many of the smaller groups, as may be seen 
by consulting the table which precedes the descriptive part of this paper. 
In comparing the Floras of different countries, we shall find that what has 
been just stated with respect to their equal distribution is fully borne out by 
facts, at least in the Northern hemisphere, whose vegetable riches have been 
more completely investigated, and that they form about the proportion of 4th 
of the phaenogamous vegetation. In the Swiss Flora, which comprises 2000 
phenogamous plants, 26 are of this family; in the Siberian Flora, of 1700 
phaenogamous plants, 21 are Gentianec ; in that of the Caucasus and Crimea, 
in 2000 there are 20; in Peru and Quito, the phenogamous plants of which 
may be estimated at 4500, there are 43 Gentianew ; and in the North Ame- 
rican Flora there are 55 out of 4081 phaenogamous plants. 
By the indefatigable researches of Dr. Wallich and Dr. Royle, the number 
of species of this family belonging to the Indian Flora has been more than 
doubled, and they now amount to about 50. Of the 14 genera into which 
they have been distributed, Canscora, Exacum, Slevogtia, Crawfurdia, Ophelia, 
and Agathotes are exclusively Indian, and the remaining 7 are common also 
to the European and Northern Asiatic Floras. Of these 50 species, 34 belong 
to the Alpine Flora, which in 3500, the number at which the phaenogamous 
plants of the Flora of Northern India may be estimated, will give a larger pro- 
portion than that above mentioned. 
