158 LOWER AMAZONS—OBYDOS TO MANAOS. Cnap. VII. 
travels, under the name of Hadrus lepidotus. It isa member of the 
Tabanidz family, and indeed is closely related to the Hematopota 
pluvialis, a brown fly which haunts the borders of woods in summer- 
time in England. The Motticais of a bronzed-black colour ; its proboscis 
is formed of a bundle of horny lancets, which are shorter and broader 
than is usually the case in the family to which it belongs. Its puncture 
does not produce much pain, but it makes such a large gash in the flesh 
that the blood trickles forth in little streams. Many scores of them 
were flying about the canoe all day, and sometimes eight or ten would 
settle on one’s ankles at the same time. It is sluggish in its motions, 
and may be easily killed with the fingers when it settles. Penna went 
forward in the montaria to the Pirarecu fishing stations, on a lake lying 
farther inland; but he did not succeed in reaching them on account of 
the length and intricacy of the channels ; so after wasting a day, during 
which, however, I had a profitable ramble in the forest, we again crossed 
the river, and on the 16th continued our voyage along the northern 
shore. 
The clay cliffs of Cararaucti are several miles in length. The hard 
pink-and-red-coloured beds are here extremely thick, and in some 
places present a compact stony texture. The total height of the cliff is 
from thirty to sixty feet above the mean level of the river, and the clay 
rests on strata of the same coarse iron-cemented conglomerate which 
has already been so often mentioned. Large blocks of this latter have 
been detached and rolled by the force of currents up parts of the cliff, 
where they are seen resting on terraces of the clay. On the top of all 
lies a bed of sand and vegetable mould, which supports a lofty forest, 
growing up to the very brink of the precipice. After passing these 
barreiros we continued our way along a low uninhabited coast, clothed, 
wherever it was elevated above high-water mark, with the usual vividly- 
coloured forests of the higher Ygapé lands, to which the broad and 
regular fronds of the Murumurt palm, here extremely abundant, served 
as a great decoration. Wherever the land was lower than the flood 
height of the Amazons, Cecropia trees prevailed, sometimes scattered 
over meadows of tall broad-leaved grasses, which surrounded shallow 
pools swarming with water-fowl. Alligators were common on most 
parts of the coast; in some places we saw also small herds of Capybaras 
(a large Rodent animal, like a colossal Guinea-pig) amongst the rank 
herbage on muddy banks, and now and then flocks of the graceful 
squirrel monkey (Chrysothrix sciureus), and the vivacious Caiarara 
(Cebus albifrons) were seen taking flying leaps from tree to tree. On 
the 22nd we passed the mouth of the most easterly of the numerous 
channels which lead to the large interior lake of Saracd, and on the 
23rd threaded a series of passages between islands, where we again saw 
human habitations, ninety miles distant from the last house at Cararaucu. 
On the 24th we arrived at Serpa. 
Serpa is a small village, consisting of about eighty houses, built on 
a bank elevated twenty-five feet above the level of the river. The beds 
of Tabatinga clay, which are here intermingled with scoria-looking 
conglomerate, are in some parts of the declivity prettily variegated in 
colour ; the name of the town in the Tupi language, Ita-coatidra, takes 
