222, CAROLINE M. HOLT 
TABLE 13. SERIES D 
Test animals 
Albino rats kept in revolving cages for thirty-three days after weaning 
Males 
OLFACTORY 
OLFACTORY BULBS: 
ANIMALS sce | werent | canara | werner | BULBS | PER CENT 
WEIGHT 
days grams mm. grams grams 
PRG tee ee ee 70 88 148 1.489 0.0191 1.30 
We Pam eh ce, St 68 eH 7 170 1.871 0.079 4.21 
Teak os 1 Sat iteah oO ey 68 140.9 176 1.831 0.085 4.63 
PR; 70 alee 185 1.784 0.085 4.79 
Average males....... 148.6 LTE 1.829 0.083 4.55 
Females 
hey EE ere 68 102.9 158 1.744 0.079 4.53 
Le ade ne) ean Sick 70 116.0 162 1.653 0.073 4.39 
Average females...... 109.5 160 1.698 0.076 4.46 
Average males and 
femaleseys [nen yee 132.9 170 1.776 0.080 4.51 
1Tungs infected. Rat undersized in every way, therefore not included in 
averages (Series C, Sick rats, p. 218). 
in controls, the olfactory bulbs of the former being, therefore, 
7 per cent heavier than those of the latter. 
4. Series E. Rats in revolving cages for ninety-eight to one hundred 
and three days 
The test animals of this group were kept in the revolving cages 
for fifteen weeks. At the end of that time, three pairs of test 
animals and one pair of controls were mated (brother to sister 
in each case). Some digestive trouble appeared in the cages of 
control rats rather early in the experiment and most of the rats 
died, while the remaining animals failed to attain a normal 
growth, so that satisfactory final controls were lacking for this 
group. But the rest of the test animals and the surviving con- 
trols were killed at the end of the fifteen weeks, measured, 
