90 
Psyche 
[April 
enough to be watching an egg through the binocular when the 
cap at the cephalic end of the egg popped loose and the nymph 
began its emergence. 4 The cap was forced up by a bubble con- 
fined by a delicate transparent membrane. After the cap was 
raised by the bubble-like device the head of the bug slowly 
advanced into the space delimited by the membrane of the 
bubble which then burst and rumpled up about the opening of 
the egg shell. This was not the post-natal molt, for when the 
bug was nearly out of the shell it was still enshrouded by a 
delicate garment that embraced each limb separately and was 
shed as the last rite in the hatching process. 
Mr. Hoffman, who studied Lethocerus americanus Leidy 
in Minnesota, failed to find the eggs in two seasons’ search. On 
July 20, 1921, at Como Park, St. Paul, Minnesota, I found an 
egg mass on a dried cattail stalk. The stalk was inclined a few 
degrees from the perpendicular and on the lower side about six 
inches above the water surface was found the egg cluster. It 
consisted of 119 eggs arranged in 6 longitudinal rows and measure- 
ed 2 inches long and Y 2 inch wide. The cattail stalk was brought 
to the laboratory and placed in an aquarium jar. The following 
morning several eggs had hatched and some were in the process 
of hatching. At this stage the photograph submitted herewith 
was made. The nymphs had the groove in the anterior femora 
which is characteristic of the genus Lethocerus and in all prob- 
ability they belonged to the species L. americanus Leidy. 
4 J. H. Fabre, Etudes sur l’instinct et les moeurs des insectes, Souvenirs 
Entomologiq-ues, 18 serie, p. 99, 1903. Gives charming account of emerging of 
Reduvius personatus. 
