Ailanthiculture. * 205 
rapidly approaching, settle on the under-surface of the abdomen 
of the female, and at once unite, being not dos-a-dos, but face to 
face. Subsequently the male hangs down in mid-air, or slips into 
the usual position, i. e. tail to tail, both clinging to the cylinder. 
The eggs are laid at night in little masses among the interstices 
of the zine, which are just large enough to allow the eggs to be 
pressed through, so that many are really deposited by the ovi- 
positor of the @ on the outside of the cylinder. Each morning 
with the finger and thumb the eggs may be easily rubbed off 
the zinc and collected, the females meanwhile being placed in a 
fresh cylinder ; while depositing the eggs the females, as is the 
case with many other insects, keep up a noisy fluttering. 
The duration of life in summer weather is eight days; but, as 
in all the stages of this insect, a higher or lower temperature 
quickens or retards vital activity, so it may be kept alive for three 
or more weeks at a temperature of 50° or less, as in November. 
Each day the eggs are to be collected and kept in a separate 
parcel. A good mode of keeping the eggs is on blotting or filtering 
paper, on a square of glass and under a glass funnel, or in a glass 
tumbler having blotting paper inside and covered at the top: the 
object being to obtain an unvarying rather moist temperature of 
about 70° F., the blotting paper should be moistened in dry 
weather once daily, and a warm place be secured. but if the sun’s 
rays fall directly upon the eggs, they run the risk of being over 
heated and dried ; in this way many beginners lose their eggs. 
The eggs will batch out in from eighteen to twelve days or 
less, according to the temperature to which they are exposed : 
thus in 1865, eggs laid May 24th, commenced to hatch out June 
11th (eighteen days); eggs laid June 6th, 7th, hatched 22nd, 
23rd (sixteen days); laid June 25th—28th, hatched July 9th 
(fourteen days); laid July 7th, 8th, hatched 21st, 22nd (thirteen 
days); while eggs laid Sept. Ist, 2nd, hatched on the 13th, and 
others laid Sept. 4th, 5th, hatched on the 16th, 17th (interval 
twelve days). 
Almost invariably the eggs begin to hatch out about 6 a.m., 
and continue to emerge in greatest quantity till 8 a.m. ; after that 
time few come out till next morning, so that they require early 
matutinal attention, and if neglected at that tender stage will 
soon perish. It is, however, easy to calculate the day of their 
birth according to the temperature, especially after the first batch 
of eyes has hatched out; the exact interval required for their 
development thereby determined, the date of the emergence of 
future batches may easily be guessed at. 
