292 Annals of the Carnegie Museum. 



made. I went down the Amazon to Belem, Para, and made two ex- 

 cursions from the latter point, one to Braganga, the other to Alcobaca 

 at the first rapid in the Rio Tocantins. These trips added many new 

 forms to the collection, more particularly parasitic catfishes, co^cilians, 

 reptiles, lepidosirens, turtles, and one fine specimen of Pipa americana 

 with eggs in its back. 



I sailed from Belem, Para, for New York on January 25, 1910. 



Much of the time of the entire trip was consumed in traveling. 

 This is especially true for the regions where primitive modes of 

 transportation were often necessary. The task was not an easy one 

 for one person. The necessary physical exertion detracts from the 

 collecting ability of anyone. However, I feel confident that from 

 this trip the Museum now has the largest collection of fishes from the 

 region between the Amazon and Patagonia. I also collected a great 

 many batrachia, molluscs, crustaceans, and aquatic insects found 

 in the region traversed by me. I also collected about thirty species 

 of snakes and several thousands of lepidoptera and coleoptera, with 

 other material of minor importance. 



I believe that the most important result of the expedition will 

 probably be the modification in some respects of the theories which 

 have been hitherto advanced in regard to the distribution of South 

 American fishes. 



Implements and Methods of Collecting. 



In order to obtain all species thorough explorations must be made 

 in a great variety of localities. Search must be instituted in swamps, 

 in lakes, along the margins of rivers, especially under the plants which 

 usually grow along the sides of all slowly flowing streams, in rapidly 

 flowing waters, in stagnant pools, in whirlpools, in deep water, in 

 clear and in muddy water, in rapids and in waterfalls, under rocks and 

 logs, in sand and mud, in hollow logs, in holes in rocky ledges and the 

 banks of rivers, in holes in dried up lagoons, in mountain rills, in 

 coastal swamps, in shady streams, and in the campos. Each of these 

 proved to be the habitat of some species not found anywhere else, 

 and methods of collecting must be selected which are suitable both to 

 the species and to its environment. The following is an account of 

 the appliances and methods which I employed, or of which I heard. 



I. Semes with Different Sizes of Meshes and a Central Sack. — 

 A seine about seventy-five feet long (the so-called " Baird Col- 



