CLAY CLIFFS 



205 



coast, eating into the crumbling earthy banks, and strew- 

 ing the river with debris of the forest. The mouth of 

 the channel lies about twenty-five miles from Villa Nova ; 

 the entrance is only about forty yards broad, but it ex- 

 pands, a short distance inland, into a large sheet of 

 water. We suifered terribly from insect pests during the 

 twenty-four hours we remained here. At night it was 

 quite impossible to sleep for mosquitoes ; they fell upon 

 us by myriads, and without much piping came straight 

 at our faces as thick as raindrops in a shower. The men 

 crowded into the cabins, and then tried to expel the pests 

 by the smoke from burnt rags, but it was of little avail, 

 although we were half suffocated during the operation. 

 In the daytime the Motuca, a much larger and more 

 formidable fly than the mosquito, insisted upon levying 

 his tax of blood. We had been tormented by it for many 

 days past, but this place seemed to be its metropolis. 

 The species has been described by Perty, the author of 

 the Entomological portion of Spix and Martins' travels, 

 under the name of Hadaus lepidotus. It is a member 

 of the Tabanidae family, and indeed is closely related to 

 the Haematopota pluvialis, a brown fly which haunts 

 the borders of woods in summer time in England. The 

 Motuca is of a bronzed-black colour ; its proboscis is 

 formed of a bundle of homy 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 for- 

 ward in the montaria to the Pirarucu fishing stations, 

 on a lake lying further 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 i6th continued our voyage 

 along the northern shore. 



The clay cliffs of Cararaucu 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 clifl is from thirty to sixty feet 



