92 HENRY H. DONALDSON 
in chart 5. In making these averages, the mean values for each 
series are taken as they stand in the tables and are not weighted 
for the number of cases to which each applies. 
When the records for the European albino cranial capacity are 
thus compared with those for the European norway, it is evident 
that there are considerable differences between the two. The 
approximate values of these differences can be determined in the 
following way: . 
If we take as the standard the body weight values of the Euro- 
pean albinos as given in each body weight group in table 13 and 
TABLE 19 
Showing the percentage values of the differences in cranial capacity between the Euro- 
pean Albinos and the European Norways of like body weights. See chart 5. The 
values in the fourth column have been read from chart 5 
| MEAN CRANIAL CAPACITY 
Albinos Norways BUSH ANON AAS 
> | grams | 2 y 7 
SCO ae Cee o dk shee 90.0 | AAS 1570 | (8.8) 
LOIS VO Siren ese c ; 130.4 i ok 1.725 3A; 0 
Dy 2 OO Peeters ones, cw 172.4 1.652 1.860 12.6 
PDO AS DAR Rats eeoteasye ole oetechs PAL SII iL. “oul 1.960 | Wt. 
P25 e100). ae Boece rere 283 .0 1.860 2.070 11.3 
US Co ay ae ee A RRL REN ei -c: Hic Gos NG Ge oO otic 12.2 
* There is in this weight group only the Paris record, see table 13 and chart 4. 
The Paris record, which runs high, raises this value and hence diminishes the per- 
centage difference given in the last column, thus slightly diminishing the general 
average. Hence the record for the 51-100 grams body weight group is omitted in 
making the final average. 
enter also for these the cranial capacity as observed, and then 
read from chart 5 the corresponding observed values for the cran- 
ial capacity of the European Norways, and enter these readings 
also in table 19, we have before us the numbers which make it 
possible to compute the percentage differences between the albino 
and the Norway records (see table 19). 
Table 19 shows the average difference between the combined 
European Albino and the combined European Norway records 
to be 12.2 per cent. 
