73 



The collection is mainly from the Amazon and the LaPlata, and their 

 tributaries. The waters of the Amazon, the LaPlata, and the Orinoco are 

 united through their tributaries, and so far as their fish fauna is concerned 

 form but one river system. The fish fauna of any one of these rivers is 

 therefore very similar to that of the others. The only genus which was 

 considered peculiar to the LaPlata fauna is Cochliodon. This genus I find 

 represented in the collection by four specimens from Marajo, near the 

 mouth of the Amazon; so there is now no genus from the LaPlata which 

 is not also found in the Amazon's system. These specimens, which be- 

 long to the species Cochliodon cochliodon, are of further interest inasmuch 

 as the genus and species has heretofore been known only from the types 

 in the Museum of Vienna. 



From the Rio San Francisco there are but four specimens, all of a species 

 common to the mouths of the east coast rivers of Brazil. The rivers of 

 southeast Brazil, which Dr. Eigenmann has shown to have a fish fauna 

 distinct from that of the Amazon to the north and the LaPlata to the 

 south, are not represented in the collection. Lake Titicaca is represented 

 by a single specimen, Pygidium rivulatura. This species, with Rhamdia 

 quelen, are the only cat fishes found in Lake Titicaca. Both of these are 

 alpine forms characteristic of the mountain streams of the Peruvian Andes. 



HOW THE COLLEGES COULD AID THE PUBLIC SCHOOLS IN TEACHING BIOLOGICAL 



subjects. By W. W. Norman. 



The Ichthyologjc features of the Black Hills region.* By B. W. Ever- 



MANN. 



[ ABSTRACT.! 



Last September I was directed by the U. S. Commissioner of Fish and 

 Fisheries to make certain investigations in Iowa, Nebraska, South Dakota 

 and Wyoming lor the purpose of determining the advisability of estab- 

 lishing one or more fish-cultural stations in those states, and if it should 

 be found desirable to establish stations in that region, to determine the 

 most suitable places for their location. 



Investigations of this kind require a more or less careful study of the 



-Published by permission of Hon. Marshall McDonald, U. S. Commissioner of Fish 

 ;»nd Fisheries. 



