
No. 426.] ULULA HYALINA LATREILLE. 425 
when the larva throws it aside and assumes its characteristic 
attitude and awaits another victim. On being disturbed the 
larva crawls away and seeks some other retreat. It often 
changes its hiding place at night, probably on account of 
scarcity of food. It always walks forward, contrary to the 
habit of antlions. The larval life lasts about sixty-two days, 
during which time the larva moults twice. It moults a third 
time inside of the cocoon, when it changes to the pupa. 
As the habits of the Ulula larva are somewhat peculiar, it 
becomes of interest to compare them with the habits of the not 
very remotely related ant-lions (Myrme- 
leonida). According to Redtenbacher, 
the Myrmeleonidz (Formicaleo, Acan- 
thaclisis, and perhaps Palpares) lie 
quietly during the day like U/w/a 
hyalina, except that the body, instead 
of being simply covered with sand, is 
buried slightly beneath the surface. 
They can walk backward as well as 
forward. At night they wander about 
in search of prey. Myrmeczlurus can 
walk forward as well as backward, but 
digs a pit like the ordinary ant-lion. 
These latter, however, never walk for- 
ward. The digging of a pit by the 
ant-lion may be but a step removed 
from the habit of Palpares in burying 
its body. The ant-lion also has the Fic. 4.— Utula hyalina. Full- 
instinct of wandering at night in pnm 
search of a more favorable situation when food is scarce. 
When the Ulula larva is full-grown it seeks some hidden place 
at night in which to pupate. Having found such a place, it spins 
a web, covering it with sand and such other small objects as 
may be at hand. It then gets inside the web and begins spin-. 
ning a cocoon. The next day it remains quiet, and at night 
continues the work. I had an opportunity of observing several 
stages of the process, as my specimen spun its cocoon against 
the side of a glass jar partly filled with sand. The side next 

