168 MEMOIRS OF THE CARNEGIE MUSEUM. 
| | 
No, | Locality. | Length, |Entomos-) Insect | radult | Invest | snnetiag,| Malacor| shes, | Vegetable 
ik Wainy cose zs 1 en eeeeeeiceeel (normatderallaace onda lAmanere sallaa aes oe 1 
2 |Aruataima..... A Oey lsc tcsec ene erences tell eter te ol oes eee lea cperecesein 2 
3 |Aruataima..... BY AI ae Par ee eel eter sa Ol aa ms alten ance ee 1 
4. (Nickaparoos jr \ SOO 7 5 cra<ccere)|levetrevetenere | ener are awe eee oe 1 
5 2 Nackaparoo.ce.s|) 250! We liars asi ereeerers eee ee | ee eee eee 1 1 
6° |Trementinal s..74) (i200 ales acelin eae leet | See eee | eee | 1 1 
ie Aruataimae: ose DAO Us ayaa: Ah” @ |W os eetavall ere rere | eae es IME Dil Bcera ne * 
8 |Nickaparooteaai) 2300 ake eeeeee re ees ee rt = | 
Oo Holmiaaees cee 751 Ulan eo rae Se he Sieve alo tee eerctens: | ne pee 1 | 1 
1OMRe dass Velhasaalie e225 eel eee 1 | | 
11 /Aruataima..... | Ge Wen. | A ec Spat Geattcnt ¢ il 1 | 
12 |Aruataima..... 2005 "Reece Sie ale ae = 
13) (Radas Velhas:.. |) USOr shee ee 15 DN alee eae es lec tare cil loemec rete | eee ns 
14 Nickaparoom sc) SO) salt syeecer Wes aes z= le eaten | 1 
15) |HntreiRioss yaaa) lide isseseer ZV Wer on ton ad | 
6M Holmige see: (22s eee 22 | 
7 SEVolm1 ame eee LOK seers OM Seecrceecr a 
Ss | Eolmiase cee | IGE) “Nsecocaue Cea glee Peerchcte: se 
19 |Packeoo....... 160 3 if | 
20) sPackeoota. ses. | 160 13 
PAL lstolbiibigonaecor IPAV livery Brae 3 
22 |Nickaparoo....| 100 
AS mukeita eee 100 i 16 
24 |Packeoo....... 90 6 
25 |Entre Rios.... | 90 | 9 | 
Total Pee ose Se ane a ee es al 
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 
larve. The larve of Diptera and of Trichoptera of several species were especially 
abundant. Of the one hundred and thirty-six insect larvee found eighty-one were 
Diptera, twenty-seven Trichoptera, six Odonata, and twenty-three uncertain. 
The Dipterous larvee resemble the larvee of Simuliwm in general shape and size. 
The Trichopterous larvee, 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 larve. The single adult 
insect found was a medium sized cricket, the one worm a small Oligochete. 
Summarizing: The small specimens had fed upon Entomostraca and insect 
larvee, those of medium size upon the larve 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 
