1913] 
Burrill, The Giant Midge, Chironomus plumosus. 
143 
absolutely undiscover able as we mounted the rising ground to¬ 
wards Eden. 
Farmers in the lake neighborhood of Oshkosh informed me 
that they called these midges “lake flies” and that the midges usu¬ 
ally made their appearance earlier in the year, but on account of 
the very dry spell which had been broken for the first time that 
summer by the slight rains encountered on the cavalry trip, the 
emergence of the “lake flies” seemed to have been delayed until 
the accumulated transformations occurred in numbers greater 
than ever. One gentleman living near the lake told me that the 
“lake fly” swarms never lasted more than a week. This accords 
with the observed facts in the previous paragraph. 
Another farmer claimed that they are troubled about Lake 
Winnebago with earlier ’’lake fly” swarms, even in spring. As 
there are so many chances to confuse Bphemeridce or smaller 
Chironomidw in the popular mind under the term “lake fly,” I can 
not accept the statement as more than a suggestion, until year¬ 
long quantitative tests on the abundance of lake insects have been 
made. This I have begun for a stretch of partly wooded bluffs 
of Lake Michigan north of East Milwaukee, but plumosus did 
not once occur there if I recall correctly the 2298 specimens al¬ 
ready contributed to the Public Museum. 
Sounds .—I noted a varying loudness in the sound produced 
by this midge under varying excitement. The initial stirring up 
of the roosting midges by the passing of the head of the cavalry 
column always brought out a louder buzz than that a minute or 
two later. This was not merely because many at once returned 
to roost, but because the swarm spread out as if to reconnoitre, 
perhaps, the passing objects. Possibly the sweaty smell of horses 
and the rising dust attracted them. It would seem that there was 
no good explanation of this variation in the degree of loudness 
except to surmise that in proportion as they were excited, they 
controlled the sound by their spiracles or by faster vibrations of 
their wings and quicker flight. The faster vibrations of their 
wings did not greatly raise the pitch of their buzz so as to run 
through a great musical range as telephone wires will in varying 
winds, but increased merely the loudness of the ordinary hum of 
such wires to a markedly stronger volume, audible above the rustle 
