$4 RIO DE JANEIRO, Tomar, 11 
and female, were chasing each other in an irregular course, 
they passed within a few yards of me; and I distinctly heard 
a clicking noise, similar to that produced by a toothed 
wheel passing under a spring catch. The noise was conti- 
nued at short intervals, and could be distinguished at about 
twenty yards’ distance: I am certain there is-no error in the 
observation. 
I was disappointed in the general aspect of the Coleoptera. 
The number of minute and obscurely-coloured beetles is exceed- 
ingly great.* The cabinets of Europe can, as yet, boast only of 
the Jarger species from tropical climates. It is sufficient to 
disturb the compesure of an entomologist’s mind, to look forward 
to the future dimensions ofa complete catalogue. The carnivorous 
beetles, or Carabidae, appear in extremely few numbers within the 
tropics: this is the more remarkable when compared to the case 
of the carnivorous quadrupeds, which are so abundant in hot 
countries. I was struck with this observation both on entering 
Brazil, and when I saw the many elegant and active forms of 
the Harpalide re-appearing on the temperate plains of La Plata. 
Do the very numerous spiders and rapacious Hymenoptera sup- 
ply the place of the carnivorous beetles? The carrion-feeders 
‘and Brachelytera are very uncommon; on the other hand, the 
Rhyncophora and Chrysomelide, all of which depend on the 
vegetable world for subsistence, are present in astonishing num- 
bers. I do not here refer to the number of different species, but 
to that of the individual insects; for on this it is that the most 
striking character in the entomology of different countries de- 
pends. The orders Orthoptera and Hemiptera are particularly 
numerous; as likewise is the stinging division of the Hymeno- 
ptera; the bees, perhaps, being excepted. A person, on first 
entering a tropical forest, is astonished at the labours of the ants: 
well-beaten paths branch off in every direction, on which an 
army of never-failing foragers may be seen, some going forth, 
* I may mention, as a common instance of one day's (June 23rd) collect- 
ing, when I was not attending particularly to the Coleoptera, that I caught 
sixty-eight species of that order. Among these, there were only two of the 
Carabide, four Brachelytra, fifteen Rhyncophora, and fourteen of the Chry- 
somelide. Thirty-seven species of Arachnid, which I brought home, will 
ve sufficient to prove that 1 was not paying overmuch attention to the gene- 
rally favoured order of Coleoptera. 
