20 Aquatic Lite 
its former position. For some moments 
the larvae rests contented and motionless 
near the surface, then suddenly it 
changes its direction and faces the other 
way. They are supplied with colored 
air-sacs, of which there are four ar- 
ranged in two pairs, which act as floats 
and may also play some part in respira- 
Larva of the Midge, Corethra 
(After Weismann - greatly enlarged) 
tion. Corethra is predaceous, and its 
transparency assists it in capturing its 
prey. It is also possible that the colored 
air-sacs draw attention, and thus at- 
tracted by these bright spots, its victims 
are less able to discern the motionless 
form until it is too late, for the next mo- 
ment the Daphne or Cyclops, as the case 
may be, is roughly seized and held in 
the mouth of the larva, from which es- 
cape is prevented by strong hairs, and 
then the juices of the victim are ex- 
tracted. 
Inasmuch as Daphne and other crus- 
taceans form the food of Corethra, it 
follows that the latter are usually found 
where the former abound. In the hot 
summer months, when transformation 
into the mature gnat-like fly takes place, 
the larvae are scarce, but it is during 
this period that Daphne is found 1 
abundance. The young Corethra hatched 
late in summer, however, remain in the 
larval state until the following spring, 
and it is therefore during the fall and 
winter months that the supply is most 
ample. Personally, I prefer Corethra as 
a fish food to Daphne, not only for the 
reason that one can lay in a supply (they 
can be kept for months in large pans of 
cold water, or even in tubs), but because 
| think they are more relished by the 
fishes, judging from the greediness with 
which they devour them, and, further- 
pedition ?”’ 
more, there is no danger of dead “bugs” 
contaminating the water in the aquar- 
ium, as in the case of an over-supply of 
Daphne, because Corethra will live in 
the tank as long as the fishes will let 
them. While their size prevents their be- 
ing fed alive to very small fishes, their 
use, however, is not limited to mature 
ones. Once a youngster is able to 
“smoke” a Corethra without strangling 
in the act, you can fairly see it grow. 
The remarkable growth attained by some 
of my exotic fishes I attribute solely to 
the diet of Corethra, and Corethra can 
be collected in winter; hence this story. 
The morning of January Ist, last, al- 
though not very early I assure you, 
found me pajama-clad answering the 
ring of my phone, and, after a “Happy 
New Year” exchange, my friend Rev. 
Rubrecht on the other end of the wire 
asked: “Do I understand that the pro- 
gram for this morning 1s a bugging ex- 
arranged. 
AvnGl 6) ihe WAS 
wor 
ae 
ws ® 
Bossa 
= 
Toes 
aS 
= 
eS 
TRS 
Brazil 
Leporinus fasciatus 
Within an hour, with buckets, nets, ice- 
pick and all the necessary paraphernalia, 
we were speeding along on a West Allis 
car for Johnson’s Woods, bug-hole 
bound. The sun shining bright, and the 
thermometer just at the freezing point, 
made a _ beautiful morning with just 
enough tinge in the air to put us on our 
mettle, happy as school boys during va- 
cation time. On arriving at our destina- 
tion, we immediately set to work cutting 
a hole. A week of zero weather had 
made the ice thick, but by taking turns 
