THE GYMNOTID EELS OF TEOPICAL AMERICA. 



173 



(8) Rhamphichthys rostratus (Linnaeus). 



Snout produced, long, and tubular; mouth quite small, terminal and inferior; 

 teeth wanting; size large, approaching six feet. 



The stomachs of three adults of this remarkable species were examined. In 

 addition to a large amount of mud they contained 612 annelids. 



The annelids were all small mud-inhabiting worms, resembUng Tubifex. The 

 eighty-two insect larvae were identified as seventy-one Diptera (a form much like 

 the "Blood Worm") and eleven uncertain. The single adult insect was a small 

 Gyrinid and the Amphipod a tiny specimen in general shape similar to Eucrangonyx. 

 The small mouth of this species (in even the largest specimen examined it barely 

 admits a lead pencil), the large amount of mud in the stomach and the nature of 

 the food indicate that this species probably feeds by sucking up quantities of mud 

 with the animals inhabiting it. 



Kaup'" in 1856 wrote concerning the genus Rhamphichthys (which then in- 

 cluded Hypopomus as well) : "Judging from the narrowness of their toothless mouth, 

 these fish must subsist on small insects." 



(1) Sternarchus albifrons (Linnaeus). 



Snout heavy and blunt; teeth in both jaws minute, conical; mouth large; size 

 moderate, not exceeding 500 mm. 



The stomach of a specimen of this species 285 mm. long contained one small 

 Characin, two freshwater shrimps, and one large insect larva (perhaps a Gomphid). 

 From the stomach of a second smaller specimen, 105 mpa. long, nineteen cnto- 

 mostraca and three large insect larvae were taken. 



(2) Sternarchus hrasiliensis Reinhardt. 



Similar to the S. albifrons, but slenderer. In the stomach of an individual of 

 this species 290 mm. long from Pirapora two small freshwater shrimps and a 

 quantity of vegetable debris were found. 



(3) Sternarchus hasemani Ellis. 



Mouth moderate; size small; otherwise much as S. albifrons. 

 Two stomachs of this species were examined. One taken from a specimen 

 160 mm. long contained twenty-seven entomostraca, two larvae of insects and 



12 Kaup, Apod. Fish Brit. Mus., 1856. 



