174. NEW YORK STATE MUSEUM 
were horned dace of about the same size, and 3 were unidentifiable. 
The 25 bullheads had.eaten at least 26 other fishes, all of piace 
the same size. 
Seven fish had eaten large dragon fly nymphs, of which 6 be- 
longed to the family Aeschnidae, and 2 had eaten Libellulidae. 
One fish only had eaten a May fly nymph and 3 had eaten small 
crawfish less than 2 inches in length. Three had eaten small fila- 
mentous algae (Spirogyra, Zygnema and Cyanophyceae) and only 
4 had eaten any appreciable quantity of silt. 
Food constituents individually considered. By far the most 
important single element of bullhead food at this time and place 
was small sunfishes. These abounded everywhere among the sub- * 
- merged aquatic plants growing on muddy bottoms. They were 
taken by small boys in minnow traps and by ourselves when col- 
lecting with sieve nets. ‘There must be fearful decimation in num- 
bers of young sunfishes in submerged pastures infested by bull- 
heads. Horned dace are also very common about the borders of 
these same water-weed patches and are likewise taken in minnow 
traps and seines. 
Although the bullheads he on the bottom, the dragon fly nymphs 
eaten did not show them to be bottom feeders. The nymphs of 
the Aeschnidae habitually climb about over the stems of water 
weeds and are rarely found on the bottom. They are protectively 
colored and are hardly noticeable when at rest, but swim away 
with a jerky gait produced by successive ejections of the water 
from the gill chamber; and when once dislodged and set going 
they are no doubt captured easily by the bullheads. The nymphs — 
of the Libellulidae are typical bottom sprawlers. Only two of these 
were eaten, however. They lie concealed amid the bottom silt and 
it is only when they are brushed out of place that they kick actively 
and are easily found. The single May fly represented, of course, 
a very insignificant part of the total food taken, but neither is it a 
bottom form. While not clearly identifiable it was certainly one 
of the climbing nymphs of the Baetinae. Crawfish diet was proven — 
by the presence of two small nipper feet. These, indeed, are 
typical bottom forms; and their habit of jumping backwards when 
disturbed and evading their enemies in a cloud of sediment, or 
fleeing into hiding under a stone, is, of course, well known to every 
one. Small quantities of algae and of silt were eaten; so small, in 
fact, that they might very well have been taken quite accidentally 
in the quest for other food, and there is no evidence whatever 
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