Page:The naturalist on the River Amazons 1863 v1.djvu/338

 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 Ceræba, 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 showing how much may be learned by noting the geographical 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 mentioned. The intermediate varieties, however, link the two together, so that they cannot be considered other-