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be paid to these conditions in order to preclude unpleasant surprises. 
Glass jars guarantee against any disappointment. 
As the larvae thrive better when the layer of food is not too 
thick, the quantity of larvae that can be accommodated in a vessel 
depends on the size of the bottom rather than on the capacity. As 
a minimum about 20 sq. centimetres (3 or 4 sq. inches) should be 
available for every 100 larvae. 
For a quick growth and early pupation the food is to be renewed 
at set times. The need of a renewal becomes clear from the crumbly 
powdery state into which the scaly structure of the bran has passed. 
The renewal is brought about most effectively by sieving. 
— 
A suitable form of sieve is found among the common kitchen 
utensils (cf. sketch). The material is usually tin, the inner side and 
bottom smooth, the latter (no wire-sieve) perforated with round holes 
of 2 or 3 millimetres diameter according to the size of the larvae. 
By shaking the sieve horizontally and quickly, the larvae remain 
in a horizontal position, have no opportunity of erecting themselves 
and are left behind on the bottom, even when their thickness is 
smaller than the diameter of the holes. 
In less than no time a large culture of some thousands of larvae 
can be separated from the bran and provided with fresh food. 
For cultures of which the larvae are very small yet, very fine 
wire-sieves should be used. This practice should, however, be stopped 
as soon as possible as the food, defiled by faeces, is not sufficiently 
cleared by these fine sieves. 
The larvae jars were covered with a glass plate. By glueing two 
strips of thick cardboard firmly on this plate, an interstice is left 
between the rim of the jar and the glass plate through which opening 
an adequate air-circulation can take place. If these cardboard strips 
are laid loose, and if by shoving away or removing the jar, such 
a strip falls with one end into it, the larvae immediately utilise it 
as a bridge to escape, and before one thinks of it, the jar is empty. 
2. The Food. 
Relying on the statement occurring here and there in the literature 
(FRENzEL p. 298) on this subject to the effect that bran should be 
a sufficient food for larvae, bran was given at the outset. Their 
growth, however, was not satisfactory. Then a substance containing 
aia ay | 
= amp 
