312 THE LOWER AMAZONS. Chap. YII. 



distance of a few minutes' walk from the settlement. 

 The first mile or two of the forest road was very- 

 pleasant ; the path was broad, shady, and clean ; the 

 lower trees presented the most beautiful and varied 

 foliage imaginable, and a compact border of fern-like 

 selaginellas lined the road on each side. The only birds 

 I saw were ant-thrushes in the denser thickets, and 

 two species of Cergeba, a group allied to the creepers. 

 These were feeding on the red gummy seeds of Clusia 

 trees, which were here very numerous, their thick 

 oval leaves, and large, white, wax-like flowers making 

 them very conspicuous objects in the crowded woods. 

 The only insect I will name amongst the numbers of 

 species which sported about these shady places is the 

 Papilio Ergeteles, and this for the purpose of again show- 

 ing how much may be learned by noting the geogTaphical 

 relations of races and closely-allied species. The Papilio 

 Ergeteles is of a velvety black colour, with two large 

 spots of green and two belts of crimson on its wings. Its 

 range is limited to the North side of the lower Amazons 

 from Obydos to the Rio Negro ; on the south side of 

 the river it is replaced by a distinct kind called the 

 Papilio Echelus. The two might be considered, as they 

 have been hitherto, perfectly distinct species, had not 

 an intermediate variety been found to inhabit Cayenne, 

 where neither extreme form occurs. The two forms 

 are as distinct as any two allied species can well be, 

 and they are different in both sexes. They are found 

 in no other part of America than the districts men- 

 tioned. The intermediate varieties, however, link the 

 two together, so that they cannot be considered other- 



