PSYCHE 
VOL. XXXI. OCTOBER 1924 
No. 5 
BIOLOGICAL NOTES ON LETHOCERUS AMERI- 
CAN US (LEIDY.)i 
By William E. Hoffman. 
University of Minnesota, St. Paul. 
Although studied since 1847 when described by Leidy, very 
little has been written about the life history or habits of this 
‘‘Electric-light Bug” or Giant Waterbug. This is rather sur- 
prising in view of the fact that its distribution is quite general 
and that it has been a favorite with biologists and naturalists 
for a long time, as evidenced by the many references to it in the 
literature. Its extreme voraciousness and the relation of this 
trait to fish culture is another reason for expecting that its life 
history might have been worked out. 
In December of 1921 several specimens of this species were 
taken from their winter quarters by the writer. They were found 
near St. Paul in a small stream connecting two lakes. The water 
in this little stream of a hundred and fifty yards in length and 
about five yards in breadth, comes out of a long concrete conduit. 
As the water leaves the conduit it has considerable current but it 
becomes sluggish before it enters the lake. The current at this 
point, however, is sufficient to keep the water from freezing 
over during winter. The bugs were found under somewhat 
varying conditions. In the center of the stream they were 
found buried some five or six inches deep in the layer of disin- 
tergrated plant material forming the bed of the stream. The 
water at this point was over two feet deep. At the edge of the 
stream they were found among Typha roots. Here the water 
was but a few inches deep and the bugs were buried to a depth of 
iPubHsted with the approval of the Director as Paper No. 481 of the 
Journal Series of the Minnesota Agricultural Experiment Station. 
