228 BULLETIN OF THE BUREAU OF FISHERIES. 
spondingly numerous. They have eaten some of every kind of nymph listed, but their 
preference seemed to be for the damselflies rather than for the dragonflies, if we may 
judge by the numbers consumed. At all events, it can easily be seen that odonate 
nymphs are more toothsome to them than any other single article of diet. 
The dragonfly nymphs recorded up to the present time are mostly Libellulides, and 
it is generally stated that gomphine nymphs escape the fish by burrowing in the sand, the 
mud, or the accumulated débris of the bottom. But even this burrowing habit does not 
save them from some fish. Of three spoonbill cats, Polyodon spathula, taken at Keokuk 
in May, 1916, 40 per cent of the stomach contents of one fish consisted of nymphs of 
Gomphus notatus. ‘The second fish’s stomach contained 1 Gomphus vastus nymph and 1 
Enallagma nymph, constituting 10 per cent of the food; the third stomach contained 1 
Gomphus vastus nymph, 25 per cent of the food. Of three moon-eye herrings, Hiodon 
alosoides, one taken March 24,1916, near Hamilton, Ill., and the other two in June at 
Keokuk, Iowa, each contained a full-grown gomphine nymph and nothing else. A river 
drum, A plodinotus grunniens, taken at Keokuk in June, contained a single gomphine 
nymph, constituting 60 per cent of its food. 
Evidence from the fishponds themselves will be more convincing than that from 
rivers, streams, or lakes, and fortunately there is an abundance of evidence from this 
very source which furnishes just the proof desired. During the year from June, 1916, to 
June, 1917, H. E. Schradieck, an employee of the Bureau of Fisheries, was engaged in 
examining the food of the fishes in the very series of ponds (series D) here considered. 
Permission has been granted to select from his manuscript records the data relating to 
odonate food, and these data have been arranged in the following table: 
Foop or FIsHES FROM PONDS IN SERIES D, Farrport, Iowa, EXAMINED By H. C. ScHRADIECK. 
v a . to od 1 ° =) 
5 3 és Sea rill eed) call |sstes 8 es g 
feqeeiias! b . | Bo ].88) 8a rey Por 
a § S| salsa] scaly. bi 
“glig| =| & |g8| es] e8| 88/88/58] 
Kind of fish. 3, gu S|) g | 83) 88) 82)=8 ou) alg 
c8@jss 5 % | S38) eS) 58) 8s) e2aleg) 8 
2 I ow 154| a8 | ao] eo] aa| SS] « 
2 1/8) 6 | 88] ea) e218 (8%) bss 
E 8 % S | 55/55) sa}/5 [3 [Seo] 8 
vA A gy 414 vA a 3° 3° < ° 
Mm.| Mm. 
. 16 
Micropterus salmoides: Largemouth black bass......... 144 3:|\ 030s 50 45 2 38 24 38 | 68.5 |...... 
: . 16 
Micropterus salmoides: Largemouth black bass......... 136 2 = 40 51 2 18 8 Ce el Ps 
: : 8 
Micropterus salmoides: Largemouth black bass......... 20 3 ap 16 I ° ° ° oy bade | Bc 
is = 20 
Lepomis pallidus: Bluegill...................eeee eee eeee 103 2 es 42 29 ° 2 ° WE ee 
. 5 33 
Ictiobus bubalis: Buffalofish..............2..0-..0-00005 22 7 78 5I ° ° ° ° o}| o I 
~ ¢ 7. 
Ictiobus bubalis: Buffalofish..............-..2..02--0 00s 350 | 5&7 = o eae ° ° ° ° os ewe eee 
: 27 
Eupomotis euryorus: McKay’s sunfish.................+ 120 8 7 4 18 ° 78 14 46 | 68.5 |....4. 
I2 
Eupomotis gibbosus: Common sunfish ................. 173 |16B ig 25 8 ° 2 ° onlis4q. (25h 
c a fi 23 
Pomoxis sparoides: Calico bass... .. 22... .2..eeee eee eee 143 8 38 30 5 ° I ° oO cua) ee 
Ictalurus punctatus: Channel cat............0000.ee eee 5 CW Ss eee 9 ° ° ° ° Oa (hi. bPacietae 
4 
Ictalurus punctatus: Channel cat.................0200+ 21 9 = FOU See teleil | sta) afaik ARO O7 SHOCeA Cricniac tater ob aT 
@ This average includes only the fish that had eaten odonate food. 
