R. C. McLean. 
340 
Horto Florestal, a Government institution designed to encourage 
the cultivation of certain useful plants. The forest on this slope, 
although not very rich in comparison with some Brazilian forest, 
has suffered no interference beyond the felling, in the past, of much 
of its big timber, a fate attending jungle everywhere within reach 
of human habitation. Nevertheless the timber is even yet heavier 
than that of many temperate forests, and the whole remains a 
perfectly presentable piece of tropical rain-forest. Its unique 
advantages of proximity to the excellent laboratories in the Gardens, 
enabled it to be used as the locale of experiments on certain ecological 
questions, the results of which will be published later. Although 
from the physiological point of view its floral diversity was not a 
matter of import, yet it is not very striking for a tropical forest, 
though greater than that of the average temperate woodland. 
There was little difficulty in collecting 50 species from among the 
ground herbs alone, and the total number of species present, even 
on this small slope, whose base might be a mile long, and its height 
perhaps 200 feet, cannot have been less than 300. 
The trees are very diverse, but the area includes a specimen 
of an almost pure palm association (Asterocarynm Ayri) not a common 
phenomenon in tropical rain-forest, which is well-known to be 
characterised by the almost perfect commixture of its constituent 
species. For future students who wish to specialise upon forest 
however, Alto-da-Serra is certainly the spot to be recommended, 
after a stay in the Gardens has introduced them to the nature of the 
Flora. It is safe to say that no man living knows the Brazilian Flora 
in the way that we understand such knowledge in a temperate 
country. What such a feat would involve will be easily understood 
when the dimensions of the Flora are indicated. 
Brazil is a country nearly as large as the whole of Europe, 
occupying almost exactly half of the continent of South America, 
and exhibiting every variety of climate and habitat, from these rain¬ 
forests to almost pure desert. Its vegetation has been as little 
altered by man as that of any other country of similar latitude in 
the world, except perhaps portions of Africa, and is of unsurpassable 
richness. 
The Federal Area in which is situated the city of Rio is not 
large, say about as large as the County of London. A large part 
of it is covered by buildings, but such is the amazing diversity of 
form, that the known Flora of the remainder of this spot is 
estimated at not less than 11,000 species, and, considering the 
almost impenetrable nature of the forest, and the desultory way in 
which collecting is done, this figure cannot exhaust the possibilities. 
Indeed, any who are enthusiasts for the capture of undescribed 
species, may obtain them within a day’s walk of the Gardens, in 
almost any direction. 
With the same reservations as before in regard to completeness, 
the total Flora of Brazil is estimated at 42,000 species—including, 
not only the huge number in the “Flora Brasiliensis ” of Von 
Martius, which is the basal work of reference, but also the large 
number variously published by independent collectors. 
What riches a systematic exploration of the lesser known 
portions of Brazil would reveal, it is only permitted to man to 
dream. Still, it is possible that such an exploration may be 
