OF THE MATTO GROSSO EXPEDITION, 1891-92. 283. 
Noy. 28th. Brilliant day; no rain; no thunder. 
29th. Fine day, only very slight shower of rain. 
30th. Early part of evening stiflingly hot; thunderstorm burst soon after 8 P.M. 
Dec. Ist. Fine day. Highest temperature 37°-3 C., just before 5 o'clock. 
2nd. Fine day, without rain. Highest temperature precisely as on preceding day. 
3rd. Fine morning. Afternoon a distant thunderstorm, with little rain. 
The above figures show the diurnal range of temperature, and bring out clearly the 
fact that, at least in November, the air is hottest after 2 P.M. ; indeed, on Nov. 29th and 
30th the maximum was not reached before 5 o'clock, and, remarkably enough, at 
7 in the evening of the latter day the mercury actually stood higher than at any hour 
of the two days preceding the 29th. A cursory inspection of the weather column 
will show a confirmation of the statement already made, that intervals of brilliant 
weather may be experienced during the wet season ; thus, for the week ending Dec. 2nd 
we find, but for a couple of thunderstorms, fine weather prevailing throughout. 
THe BOTANICAL GEOGRAPHY OF BRAZIL. 
For the earliest generalizations of any practical value bearing upon the botanical 
geography of Brazil we must go to Von Martius, whose views were adopted in those 
earlier volumes of his great ‘Flora Brasiliensis’ which were published before the 
eminent traveller’s death, and are still recognized in the various parts issued and now 
issuing. Martius distinguished the low watered plains of Brazil as the Naiad region, 
while to the tropical mountain forests of Rio de Janeiro and the eastern coast he 
applied the term Dryad region. The back parts of the provinces of Bahia and 
Pernambuco have an exceedingly hot and dry climate, which the uplands of Ceará, 
Piauhy, and the neighbouring provinces also share; this is the Hamadryad region. 
An Oread region is also distinguished; it comprises the uplands of Minas Geraes, 
Goyaz, Matto Grosso, and Sao Paulo. The small portion of the country lying south 
of the Tropic of Capricorn Von Martius distinguishes as the Napea region. In the year 
1872 appeared Grisebach’s ‘ Vegetation der Erde,’ a work which may fitly be called 
the first modern attempt to grapple with the problems pertaining to the distribution 
of plants over the whole globe. For the bulk of Brazil Grisebach recognizes only 
two regions; his extra-tropical part he includes in his Pampas region. The northern 
of these two regions, or Amazon region, corresponds with the Naiad region of Von 
Martius; its northern limit runs nearly parallel with and close to the Equator, while 
in the south-east its boundary includes Ceará, Piauhy, and Maranháo, and is continued 
westward to the neighbourhood of the Andes, but without anywhere reaching the 
limit of 10° S. latitude. The rest of tropical Brazil Grisebach unites into one large 
Brazilian region. Engler’s * views are somewhat different. He objects to the inclusion 
in the Amazon region of the dry Piauhy, Ceará, and Maranhao uplands, and he sees 
no reason why the whole of the country drained by the Amazon and Tocantins rivers 
and their feeders should not be included in one province f, with which he throws 
* © Versuch einer Entwickelungsgeschichte der Pflanzenwelt.’ 
+ He excludes, of course, the strip of country bordering on the Andes ; this constitutes his Subandine province. 
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