195 
more fat, in the form of rusk, was added by way of trial. According 
to the number of larvae one or more whole rusks were put in the 
larvae jars. The creatures took them with eagerness. For comparison 
some other jars were provided with some slices of peat. Also under 
these, the larvae gather up and they make large passages in the 
peat. It is not probable that the peat should serve them for food. 
After this experience the following comparative experiments were made. 
Six jars were provided with: 
Meer only bran . .- . See ee AN RER la 
N°. 2 bran on a layer of iat Pe ic and ee EO Me HT 
N*. 3 only meal (flour). . . EC a aes, ETE 
N°. 4 meal (flour) on a layer of LE BNN SI a CME 
an th Pus once eo ar Rat elke oe (BR): 
N°. 6 meal (flour) with rusk . . (M.R.). 
In each jar 300 eggs were placed in iet same hand (May 27— 
June 21 1915). Down to February 10, 1916 included, the following 
numbers of pupae were collected: 
TABLEVE 
| Number of! Pupae Number of 
Number | End | Larvae collected till, Pupaein Per- 
of jar. 7" | obtained Febr. 10.1916) cent. of the 
from 300eggs incl. larvae. 
1 B. 250 0 — 
2 B. P. 112 0 — 
3 M. 247 3 1.2 0, 
4 M. P 192 13 67 
5 Bake. 206 43 208 
6 M. R 225 36 168 
| | 
From the foregoing figures, though provisional, the following 
_eonclusions may be drawn. 
1. An exclusive nutrition of bran is inadequate to a normal growth 
of the larvae. 
2. An exclusive nutrition of meal is better than bran alone. 
3. An addition of rusk to meal or bran promotes the development 
of the larvae considerably. 
4. An addition of rusk gives a better result to bran than to meal; 
the pupation is 4 per cent higher. 
This provisional result was again tested in the following manner. 
13* 
