252 NAOKI SUGITA 
TABLE 5 
The cortical thickness at the corresponding parts of the cerebral hemisphere in dif- 
ferent mammals, quoted from Brodmann (’09). According to his nomenclature, 
area precentralis = type 4, area frontalis agranularis = type 6, area parietalis = 
type 7, area occipitalis = type 17, area hippocampica = type 28, and area retro- 
splenialis = type 29, as given in his ‘Hirnkarte’ (Brodmann, ’09) 
mn 1 1S] 
a m e Zz a 
mn 4 
fod est eee ie ees |) ae eee 
SPECIES 3 a a o< a Py 8 5 a 
al a iS) gr Ls im o8 
A 3 B Be 3 5 Sy Ee ay 
5 eS A a A ° x <n om 
» 5 < <% < < < ag ab 
a < a gQ < Q a Q 2 x Re 
° fon] & fof (ot <i & > 
Q 4 < < < < < < < 
; grams grams mm. mm. « mm. mm. mm. mm. mm. 
Homo sapiens (man)} 60,000} 1,400/3.0-4.5/3.0-3.8/3.08/2.3-2.6/2.5 | 2.3 |3.0 
Cercopithecus (long- 
tailed ape)....... 2,500} 85 3.0 De NDQsOL Pe Ga ee eo 
eMuUry eect ees 1,800} 23 2.3 203) MGrl Abba soy 11S adie ie 
Hapale(marmoset). 200 8 Weis || alee inlay Ibe Le alee [fil a) 
Pteropus edwardsii 
(vampire bat).... 375 Gols Lag LaG (flee 1.76 |1.52)1.4-1.76)1.66 
Erinaceus euro- 
paeus (hedgehog) AO! S385 |) TAYE) ok eH ES LO), Math fl Gil 
Cercoleptes caudi- 
FOU) ce peepee one 2,000 DAZ: 1 2.0 se | AS) ESOS Tes, HESo 
Lepus _cuniculus 
(nabs bith’. “ioe 2,200} 10 Pall 25331252)| 18° 1122>|0.8-1.5 1509 
Spermophilus citil- 
lus (ground 
SQUisrel)'. -...4e 200); 92225)" 221 DAS NWS) dicot eo Onvome lees 
Macropus- gigan- 
teus (kangaroo)..| 5,000} 25 |2.8-3.1 PAP NO lar Il Tbe ees 
Reviewing this table, it is readily seen that, within each 
order, the animal which has a greater brain weight shows also a 
greater cortical thickness, but a fixed relation between the 
brain weight and the cortical thickness has not been here re- 
vealed. In different orders, this relation is not true; the lemur 
and the kangaroo have a similar brain weight (23 to 25 grams), 
