168 



MEMOIRS OF THE CARNEGIE MUSEUM. 



It will be seen from the preceding table that a correlation exists between the 

 kind of food taken and the size of the eel. The twenty-five specimens may be 

 divided into three groups. The first of these groups includes all of the specimens 

 between 240 mm. and 430 mm. in length. These fed almost entirely upon large 

 Crustacea and fishes, only a few insects having been eaten by three of the smaller 

 ones. Of the eleven malacostraca one was an Isopod, the rest freshwater shrimps. 

 Two of the three fishes found were small Characins; the third, which was found in 

 the stomach of No. 4, was a G. carapo 90 mm. in length. The second group, those 

 specimens between 100 and 240 mm. in length, contained little else than insect 

 larva;. The larvae of Diptera and of Trichoptera of several species were especially 

 abundant. Of the one hundred and thirty-six insect larvse found eighty-one were 

 Diptera, twenty-seven Trichoptera, six Odonata, and twenty-three uncertain. 

 The Dipterous larvse resemble the larvae of Simulium in general shape and size. 

 The Trichopterous larvse, which had been swallowed with the case uncrushed, 

 were forms whose cases were made of small particles of sand, some being straight, 

 others cochlear in shape. Only fishes under 100 mm. in length had eaten Ento- 

 mostraca. These had also taken small parts of insect larvse. The single adult 

 insect found was a medium sized cricket, the one worm a small Oligochsete. 



Summarizing: The small specimens had fed upon Entomostraca and insect 

 larvse, those of medium size upon the larvse of insects and large Crustacea, the 

 largest upon large Crustacea and fishes. One individual was a cannibal. None of 

 the food was from the air, the land, or the surface of the water; a large per cent of 



