88 
For such larvae as feed upon growing- foliage, it is absolutely essen- 
tial to change the food every twenty-four hours, since while they will 
feed, in the absence of fresh food, upon drying leaves, this results in 
constipation and probable consequent febrile symptoms. At the time 
of renewing the food it is essential to carefully wipe out the jars or 
the cages. 
Clean, sterilized, and sifted sand is perhaps the best substance to 
use in the bottom of breeding cages and for most larva? which hiber- 
nate underground to enter for pupation. After such insects have gone 
down it should be kept reasonably moist by occasional sprinkling, and 
a free current of air should be admitted to the surface. 
Of all larva? none are more difficult to rear than those of Tenthre- 
dinidse. Their inouth-parts seem to dry unless constantly lubricated 
by the saliva induced by mastication, and once dried the larva usually 
dies. So when received by mail from a distance it is usually impossible 
to rear them. They wander restlessly over the food, leave it. crawl 
about and die. Even when transferred, with their food, directly to the 
breeding cage they are usually dissatisfied and restless. Fresh food 
must constantly be supplied, and if possible they must not be allowed 
to descend to the surface of the sand, or the latter must carefully be 
covered with paper or blotting paper ; for if they once close their pro- 
legs on a grain of sand, they hold it convulsively and it is almost im- 
possible to dislodge it. so that they are practically unfitted for again 
clasping a twig. 
Acridiidae are most difficult insects to rear. Confined in a breeding- 
cage of the ordinary dimensions, they feed little and are apt to fatally 
exhaust themselves in futile efforts to escape. Therefore they should 
be inclosed in a large gauze- covered inclosure, say 3 feet square, and 
in the earth should be growing not only grass but also weeds of various 
sorts, such as Astragalus, Amaranthus, and Eumex. Their close allies 
the Locustida? are, on the contrary, very easy to rear in confinement and 
need only be given an occasional supply of fresh food to flourish 
even in close quarters. So also with the Phasmatidae and Mantidae. 
The latter require no moisture whatever, beyond that which they get 
rrora the bodies of their victims. 
In rearing hymenopterous parasites the jar should be tightly closed 
and an occasional narrow strip of moistened blotting paper inserted. Or 
they may be inclosed in glass tubes with tight absorbent cotton stoppers,, 
the stoppers being occasionally moistened. Bees, such as Megachile. 
need very little moisture and give little trouble in rearing. Stalk- 
borers of all kinds may. as a rule, be kept perfectly dry or only moistened 
somewhat every two or three weeks. Plant-feeding Heteroptera need 
simply plenty of fresh food and will take care of themselves, with com- 
parative indifference as to their surroundings. Certain other coleop- 
terous larva?, such as most of those of the adephagous series, should be 
