194 Trans. Acad. Sci. of St. Louis 
the ant-lion larvae must get what they can. With the 
ant-lions, it is either a feast or a famine—when food 
is plentiful, they develop to maturity quickly; when it 
is scarce, they do not die, but combat famine with pa- 
tience. Herein Mother Nature anticipated Victor Hugo, 
who said: ‘‘A clock does not stop short at the precise 
moment when the key is lost!’ 
An interesting detail in their method of feeding was 
noticed when a Grapta caterpillar was dropped into one 
of the pits. The ant-lion captured it and promptly 
sucked out the juices; five minutes later it was discov- 
ered that the ant-lion had also snipped the body-wall 
and was dragging the viscera out through the aperture. 
The only relation these Jarvae had to the other inhab- 
itants of the unit, was to eat any insects, such as weevils 
and caterpillars, which, through accident or misfortune, 
fell into their pits. I noticed also that occasionally their 
pits served as good starting points for the burrows of 
the Larrid wasp, Tachysphex terminatus. The Antho- 
phora bees were probably too big game for them, but 1 
did find one struggling with a dead bee in the pit. 
Whether the dead bee had fallen into the pit, or the ant- 
lion had actually attacked and killed a live one which 
eame within its reach, I do not know. 
One ant-lion passed five weeks in the pupal stage; hav- 
ing spun the cocoon on ‘April 16, 1921, it emerged as 
adult on May 24, A second one spent six weeks in that 
stage, or from April 6 to May 25, 1921. 
House-Spider, Theridion tepidariorum Koch [J. H. 
Emerton]. 
These house-spiders should be reckoned as among the 
original inhabitants of the unit, since their webs were 
