PARTS OF BRAIN IN NORMAL AND UNDERFED RATS 5G 
TABLE 2 
Number, sex, weight, and length, with weights of the brain and its various parts in 
normal and underfed rats at different ages 
GROSS OLFAC- 
NUMBER, SEX, AND AGE OF RATS izopr. Leto | BRAIN | SESe’ | srem Baie pony, 
grams mm. grams 
8 o&', Control,-newborn.... 4.97} 49.1! | 0.2106) 0.1375} 0.0622} 0.0079) 0.0055 
1 Nestitchyoidays tis: 4.7 | 56.0 | 0.3653} 0.2481) 0.1085) 0.0213) 0.0151 
i Mest. co) (Otdaye onc: 5.5 | 56.0 | 0.3872} 0.2724) 0.0940) 0.0232) 0.0118 
Tl GREK Ke GROCERIES age ao os 4.6 | 55.0 | 0.38743} 0.2563) 0.1027) 0.0213) 0.0150 
iL Westin tala ated ope 4.8 | 53.0 | 0.4711] 0.3368) 0.1014) 0.0307) 0.0154 
IeMesti ct wl2daysasese ss. 5.8 | 57.0 | 0.5348] 0.3742] 0.1143] 0.0356) 0.0246 
ipMestacH poor asta cie as 5.0 | 57.0 | 0.4790) 0.3413) 0.1134) 0.0335) 0.0192 
tt Nest. ct elaidayes ese ac. 5.5 | 59.0 | 0.5404) 0.3845] 0.13834) 0.0346) 0.0242 
le Mestrod mad avisuccsae 5.5 | 57.0 | 0.4920) 0.3464) 0.1062) 0.0334) 0.0220 
iiMest: ot; 14; dayse cs 4: 5.8 | 60.0 0.4571) 0.3247) 0.1053) 0.0291) 0.0180 
Average, 10.6 days...... 5.24] 56.7 | 0.4557| 0.3205} 0.1088) 0.0292) 0.0184 
An OP ANG wDOLmM use a oe 4.65| 47.5? | 0.2046) 0.1323) 0.0611! 0.0074] 0.0048 
eesti eno wd aSeney ee 4.9 | 54.0 | 0.3603) 0.2549) 0.0999) 0.0205) 0.0149 
ieReSta Ori lladayse.. oa. 4.0 | 52.0 | 0.3728} 0.2564) 0.1033) 0.0212) 0.0154 
I PMEStAC LoL ase mae 4.8] 55.0 | 0.4434) 0.3139) 0.1018) 0.0262) 0.0180 
MNES ts Om 2icdayisere., ve 5.0 | 54.0 | 0.5079] 0.3444| 0.1068} 0.0328) 0.0204 
iGdest, Op lavdayse, esse. 5.0 | 56.0 | 0.4019} 0.2892) 0.0872) 0.0256) 0.0142 
femest; C218 dayash.. . 5... 5.1 | 54.0 | 0.5212) 0.3732) 0.1180) 0.0415) 0.0216 
Average, 12 days....... 4.8 | 54.1 | 0.4346} 0.3053) 0.1028) 0.0280] 0.0174 
5 Control o&, 9 days...... 10.2 | 63.0 | 0.6309] 0.4589} 0.1280) 0.0396) 0.0181 
OrVest tot 22\dayese. 1... 10.4 | 67.8 | 0.8837| 0.6169) 0.1578) 0.0956) 0.0265 
4 Control 9, 9.5 days..... 9.6 | 63.3 | 0.6845} 0.4830) 0.1282} 0.0497| 0.0212 
4 Test. 9 ,) 22) days. .../... 9.6 | 65.9 | 0.8444] 0.5894) 0.1477) 0.0896) 0.0229 
1 Control 6, 9 days...... 12.0 | 69.0 | 0.7324) 0.5304} 0.1340) 0.0556} 0.0240 
Ii West ct, oodaysr....... 12.0 | 77.0 | 0.9544} 0.6312) 0.1856} 0.1210) 0.0410 
1 Average of 7 individuals. 
2 Average of 3 individuals. 
On comparison with the brain of the newborn rat (A and A’), it is evident that 
during underfeeding (maintenance) not only the brain as a whole, but also the 
olfactory bulbs and tracts, cerebral hemispheres, colliculi, cerebellum and floc- 
culi, tuber cinereum, pons, and medulla continue to grow in young rats in spite of 
practically no change in body weight for 20 days. Comparison with the normal 
brain at 20 days (C and C’), however, shows that the growth of the various parts 
of the brain mentioned above, while considerable, nevertheless has been greatly 
retarded. 
C and C’, dorsal and ventral view, respectively, of brain of normal rat at 20 
days of age. Body weight, 17.5 grams. Brain weight, 1.047 grams. X 3. 
