1896.] EXPEDITION ON THE LOWER AMAZON. 771 
Turning now to the harvest of the expedition, I may say at 
once that the collections we brought home consisted almost entirely — 
of Arthropods. Mr. Pickard-Cambridge naturally devoted him- 
self more particularly to Spiders, since they are his speciality, 
while I similarly looked after the Insects. But, apart from this, 
Mammals, with the exception of Bats and Dolphins, were con- 
spicuous by their absence, while, as we had no one to assist us in 
skinning, it was impossible, in the time at our command, to do 
very much among the Birds. Reptiles and Amphibians were by 
no means abundant, and such as were met with prove, with a 
single exception, to belong to well-known and widely distributed 
forms. Among the Fishes it might have been possible to do some- 
thing, but unfortunately a trap which I had brought with me was 
lost, owing to the breaking of a rope the second time it was put 
overboard. 
Mammats.—The Lower Amazon and the adjacent waterways 
(including the Para River and the maze of connecting channels) 
are shut in by dense forests, in which the naturalist unaccom- 
panied by a guide might easily lose his way should he venture far 
from the narrow paths used by the rubber-gatherers. Around the 
small towns, however, there are more or less extensive clearings, 
while at Santarem there is a considerable tract of open country 
(“campo”). But in the forest itself,in the short time at my 
disposal, it was never possible to penetrate more than a few 
hundred yards from the river’s brink. The entire absence of 
Mammals, or even of any traces of Mammals, in the forests near 
the shore of the river was most striking. I had included in my 
outfit a large number of traps of various kinds, but never found the 
slightest opportunity of using them. The shores of the Parana 
de Buyassu and the other narrow channels between the Para 
River and the Amazon are low, and the forests near the water are 
consequently exceedingly swampy, which may in some measure 
account for the absence of Mammals at this particular spot ; but 
once in the Amazon itself the shores are much higher, though in 
many places, no doubt, still liable to submergence at the height of 
the rainy season. 
A fair number of Bats was collected from time to time, most 
of which flew on board the ship, but in the absence of Mr. Oldfield 
Thomas they have not yet been examined, so that I am unable to 
say anything about them. 
Freshwater Dolphins (Inia geoffroyensis and Sotalia tucusxt, or 
S. fluviatilis) were exceedingly common, especially in the neigh- 
bourhood of the Parand4 de Buyassu and in the furo, or narrow 
channel leading up to Monte Alegre. The former species, which 
is much larger than the other and generally appears to be about 
seven feet in length, is either wholly pink or flesh-coloured or else 
entirely black or black above and pink beneath. I often wondered 
whether this difference in colour is sexual, as the two kinds are 
nearly always seen in company; anyhow the point would be well 
