454 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 17 
viduals which would constitute the capacity of the case for each differ¬ 
ent species. 
Cactus of a nature suited to each particular insect species was care¬ 
fully selected so as to be free from all insects and diseases (except 
possibly Hendersonia opuntiae which is present on practically every 
plant in the southwestern cactus area). The presence of cactus an- 
thracnose, for instance, would cause havoc among the cactus plants 
when passing through the tropics and the reduction of cactus would re¬ 
act against the insects being shipped. It is needless to go into detail re¬ 
garding these specific points as related to each species, and I will let it 
suffice to mention one instance of a moth ( Mimorista flavidissimalis 
Grote) with a very short life-cycle. This insect feeds only upon the 
very young, tender joints of cactus (“nopalitos”) and reaches the adult 
stage about 28 days after egg deposition. The insects consigned from 
the United States to Australia must usually remain in the cases from 
five to six weeks. In other words, even if shipped as eggs the adults 
would emerge enroute and would require nopalitos on which to oviposit. 
Accordingly, cases to contain Mimorista were always packed with a 
sufficiency of nopalitos to insure the development of the eggs or larvae 
sent, and provision was also made for oviposition of the issuing moths. 
Old stumps of cactus which have been heavily pruned and have lain 
unrooted for several weeks, will begin to send out many young joints 
shcrtly after being supplied with heat and mositure. Such stumps were 
also included in cases to contain Mimorista , and they made available a 
fresh supply of nopalitos enroute for oviposition and development of the 
second brood of larvae. 
The number of insects assigned to a given shipping case depended 
upon the amount of cactus in the case and the relative destructiveness 
of that particular insect species. It was highly important, then, that 
every possible piece of cactus be fitted into each case. The clean cactus 
selected from the field as suitable for a particular species, underwent 
further selection in the process of fitting together odd-shaped pieces to 
secure the maximum amount in the case. This selection and close 
packing of several cases made the preparation of a consignment a most 
tedious matter. The photographs in Plate 8 show different stages in the 
packing of cases for Melitara junctolineella Hulst and M. prodenialis 
Walker respectively. 
To keep the cactus fresh and enable it to root itself enroute a material 
with high qualities of water retention was needed in which to surround 
the cut ends of the pieces of cactus. Soil could not be used because of the 
