OF THE MATTO GROSSO EXPEDITION, 1891-92. . 285 
be felt at stray plants characteristic of the Amazonian country turning up near Cuyaba ; I 
did not meet with many such plants, but there is a certain percentage of that element in 
the flora, as will directly be shown. 
For the purpose of this and the following chapters, as also in the systematic portion 
of the present memoir, I have employed certain geographical expressions which must 
now be explained. The term “ Bras. Or.” is used to denote the whole of the eastern and 
south-eastern part of the country, from Ceará and Piauhy to Rio Grande do Sul, including 
Bahia and the neighbouring littoral provinces, Minas Geraes and the southern end of 
Goyaz. By “ Amazonia” I mean the whole of the Amazon and Tocantins basin with 
the exception of the former’s extreme western end, which comes within the Subandine 
province; excluding, too, Northern and Central Goyaz, a district in my opinion certainly 
forming part of the North-Brazil-Guiana province, but kept distinct as tending to show, 
more satisfactorily than would otherwise be the case, the relations of the Matto Grosso 
floras to the flora of different portions of the above-named province. For the same 
reason Guiana-—restricted to English, French, and Dutch—receives separate mention. 
The other districts are political, as it is sometimes extremely difficult if not impossible to 
discover of what botanical province a given plant is a denizen—a remark of special 
reference to the north-western parts of the continent. 
With a view to making the following statements as wide in their application as possible, 
I have diligently sought out the affinities of the species considered to be new, entering 
the result within brackets at the end of each description, but in these cases using italics. 
On the other hand, the known distribution of a species already described is given ina 
similar way, but without italics. This method of ascertaining the affinity of a new species, 
and considering such affinity when found as evidence of phytogeographical value, has 
much to be said in its favour, especially in the case of one who has exhaustively mono- 
graphed the genus to which is referable any given plant so dealt with; though, in less 
favourable circumstances, explicit reliance upon an author's conclusions can hardly be 
expected. however laboriously he may have reached them. The only alternative is, when 
tabulating one’s results, to omit all the new species from the calculation, an unsatisfactory 
method when, as in the present case, a large number of species are new. 
Of the flora now to be considered, as of most of the other floras, the chief factor is the 
Tropical American, consisting, that is to say, of species having a wide range through the 
American, or at least South- American tropics. No less than thirty-five per cent. of the 
flora is of this nature *. There is also a large contingent (twenty-six per cent.) of types 
occurring both in Eastern Brazil and in some part of the North-Brazil-Guiana province. 
The element next in importance is the East Brazilian (twenty-four per cent.) ; while the 
North-Brazil-Guiana province is represented to the extent of only ten per cent. Other 
small elements of the flora are the East-Brazil-Paraguay, the East-Brazil-Goyaz—Paraguay, 
and the East-Brazil-Amazonia-Paraguay, together making up between two and three 
per cent. In accordance with Engler’s scheme, the first of these should be included in 
the South-Brazilian flora, and the two latter dealt with in the enumeration of species 
* Here and elsewhere decimals are omitted. 
