Cuap. VII. MIMETIC BEETLES. 177 
The borders of the forest yielded me more insects also than the 
shady central pathways. A few species occurred which I had pre- 
viously found at Obydos and Serpa, but certain kinds were met with 
which are not known in any other part of South America. The small- 
leaved bushes and low trees on the skirts of the forest and along the 
more open pathways were sparingly tenanted by a variety of curious 
phytophagous beetles. None of these offered any remarkable feature, 
except perhaps the species of Chlamys. These are small beetles of a 
cubical shape and grotesque appearance, the upper surface of their 
bodies being studded with tubercles. They look like anything rather 
than insects: some of them are an exact imitation of the dung of cater- 
pillars on leaves ; others have a deceptive likeness to small flower-buds, 
galls, and other vegetable excrescences, whilst some large kinds are 
like fragments of metallic ore. They are very sluggish in their motions. 
and live in the most exposed situations on the surface of leaves ; their 
curious shapes are therefore no doubt so many disguises to protect 
them from the keen eyes of insectivorous birds and lizards. A nearly 
allied group, the Lamprosomas, of which several species occurred in 
the same places, have perfectly smooth convex bodies ; these glitter 
like precious stones on the foliage, and seem to be protected by the 
excessive hardness of their integuments. The Eumolpide and Galeru- 
cide, two groups belonging also to the leaf-eating family, were much 
more numerous than the Chlamydes and Lamprosomas, although 
having neither the disguised appearance of the one nor the hard 
integuments of the other; but many of them secrete a foul 
liquor when handled, which may perhaps serve the same purpose 
of passive defence. The Chlamydes are almost confined to the 
warmer parts of America, and the species, although extremely 
numerous (about three hundred are known in collections), are nearly 
all very rare. It is worthy of note that mimicking insects are very 
generally of great scarcity; that is, few examples of each species. 
occur in the places where they are found, and they constitute groups 
which are remarkable for the strongly-marked diversity and limited 
ranges of their species. 
After we had rested some weeks in Barra, we arranged our plans for 
further explorations in the interior of the country. Mr. Wallace chose 
the Rio Negro for his next trip, and I agreed to take the Solimoens. 
My colleague has already given to the world an account of his journey 
on the Rio Negro, and his adventurous ascent of its great tributary the 
Uapés. I left Barra for Ega, the first town of any importance on the 
Solimoens, on the 26th of March, 1850. The distance is nearly 40c miles, 
which we accomplished in asmall cuberta, manned by ten stout Cucama 
Indians, in thirty-five days. On this occasion, I spent twelve months in 
the upper region of the Amazons ; circumstances then compelled me to 
return to Parad. I revisited the same country in 1855, and devoted 
three years and a half to fuller exploration of its natural productions. 
The results of both journeys will be given together in subsequent 
chapters of this work ; in the meantime I will proceed to give an account 
of Santarem and the river Tapajos, whose neighbourhoods I investi- 
gated in the years 1851-4. 
12 
