APPENDIX. No. V. 42| 
any conclusions concerning the proportional numbers of the three primary 
divisions, or of the principal natural orders in the country in which it 
was formed. 
Its value in this respect must depend on the relation it may be supposed 
to have to the whole vegetation of the tract examined, and on the probability 
of the circumstances under which it was formed, not materially affecting the 
proportions in question. 
Its probable relation to the complete Flora of the country examined, can at 
present be judged of only by comparing it with collections from different 
parts of the same coast of equinoctial Africa. 
‘the first considerable herbarium from this coast, of which we have any 
account, is that formed by Adanson, on the banks of the Senegal, during a 
residence of nearly four years. Adanson himself has not given the extent of 
his collection, but as he has stated the new species contained in it to be 300,* 
it may I think, be inferred, that altogether it did not exceed 600, which is 
hardly equal to that from Congo. Limited as this supposed extent of Adanson’s 
herbarium may appear, it is estimated on the most moderate calculation of 
the proportion that new species were likely to bear to the whole vegetation 
of that part of equinoctial Africa, which he was the first botanist to examine ; 
» allowance being at the same time made for the disposition, manifested in the 
account of his travels, to reduce the plants which he observed to the nearly 
related species of other countries. 
From the herbarium, and manuscripts in the library of Sir Joseph Banks, it 
appears, that the species of plants collected by Mr. Smeathman at Sierra 
Leone, during a residence of more than two years, amounted to 450. 
On the same authority I find that the herbarium formed in the neighbour- 
hood of Cape Coast by Mr. William Brass, an intelligent collector, consisted 
of only 250 species. 
And I have some reason to believe, that the most extensive and valuable 
collection ever brought from the west coast of equinoctial Africa, namely, that 
formed by Professor Afzelius, during his residence of several years at Sierra 
Leone, does not exceed 1200 species: although that eminent naturalist, in 
the course of his researches, must have examined a much greater extent of 
country than was seen in the expedition to Congo. 
From these, which are the only facts I have been able to meet with respecting 
* Fam. des Plant. \. p. cxrvi. 
