Kathleen V. Ryley and Julia Bell 
397 
measured. Finally to test the extent to which K. V. Ryley's methods were finally 
standardised, a third measurement of the male Whitechapel crania was made four 
months later than B, namely C in December, 1912. In the case of C the same 
50 crania exactly were remeasured*. There now resulted a very close accordance 
between all the measurements absolute and indicial. It will be noticed on 
examination of the Table that : 
(i) The error in the value of the simotic index due to variation of personal 
equation never exceeds a point. 
TABLE III. 
Comparison of Measurements on the Nasal Bridge made at intervals and on 
different samples. 
Series 
Meso- 
dacryal 
Chord 
(DC) 
Meso- 
dacryal 
arc (DA) 
Simotic 
Chord (SC) 
Simotic 
Subtense 
(SS) 
Meso- 
dacryal 
Index /3 
Meso- 
dacryal 
Index a' 
(from ft) 
Simotic 
Index (S) 
Bemarks 
Gaboon, 1864, A $ 
24 
5 + 
2 
33-5 + 
•3 
9-16 + 
■26 
2-87 + 
•11 
42-7 + 
9 
45 '4+ -6 
30 
8 + 
•9 
Same 
» B$ 
23 
2 + 
2 
32-4 + 
•3 
9-43 + 
■26 
2-88 + 
•11 
40-0 + 
8 
43-6+ -5 
30 
9 + 
•9 
! 
crania 
„ A? 
23 
1 ± 
3 
32-3 + 
•4 
9-55 + 
•28 
2-68 + 
■10 
44-8 + 1 
3 
46-7+ -8 
28 
7 + 1 
■o 
Same 
„ 
Congo, A £ 
22 
5 + 
3 
31-8 + 
•4 
9-88 + 
•29 
2-68 + 
•11 
42-0 + 1 
3 
44-9+ -8 
27 
7 + 1 
•o 
! 
crania 
24 
•4 + 
3 
32-8 + 
•4 
9-44 + 
•21 
2-38 + 
■08 
34-5 + 
9 
39-6+ -6 
25 
6 + 
■8 
1 
Same 
» B$ 
23 
9± 
3 
32-4 + 
•4 
9-80 + 
•21 
2-48 + 
•09 
35-5 + 
8 
40-5+ -6 
25 
6 + 
■7 
1 
crania 
„ A$ 
23 
5 + 
3 
32-2 + 
•4 
9-46 + 
■33 
2-31 + 
■11 
36-8 + 1 
0 
41-5+ -7 
25 
2 + 1 
■3 
Same 
„ 5? 
23 
•3 + 
3 
30-8 + 
■3 
9-72 + 
•35 
2-41 + 
•12 
32-6 + 
8 
38-6+ -6 
25 
7 + 1 
•4 
i 
crania 
Egyptians, A$ ... 
21 
■5± 
2 
34-5± 
■4 
10-58 ± 
•18 
4-67 + 
•10 
61-3+1 
5 
57-0 ± -9 
44 
8 + 
■8 
Different 
B$ ... 
A2 ... 
21 
20 
5 + 
•4 + 
2 
2 
35-3 + 
32-4 + 
•2 
•2 
10-42 + 
10-76 + 
•17 
•17 
4-63 + 
411 + 
■10 
■09 
65-0+1 
59-3 + 
3 
9 
59-4+ -8 
55-9+ -6 
44 
38 
4 + 
6 + 
•7 
•7 
! 
\ 
samples 
Different 
5? ... 
20 
6± 
3 
32 -0± 
■3 
10-84 ± 
■16 
3-97± 
•09 
56-0±l 
1 
53-9± -7 
36 
9± 
•8 
) 
samples 
English, A £ 
BJ ... 
22 
21 
6 + 
5± 
2 
2 
35-1 + 
34 -8 ± 
■3 
•3 
9-52 + 
9-38± 
•17 
•17 
4-74 + 
4-68± 
■11 
•10 
56-2+1 
62-7±l 
3 
2 
53-9+ -8 
58-0±-7 
50 
50 
7 + 1 
8±1 
•2 
•2 
1 25% 
> different 
i crania 
„ A$ ... 
„ - 
20 
20 
9 + 
6± 
2 
2 
31-9 + 
31 "5 ± 
•3 
•3 
8- 98 + 
9- 10± 
•18 
•17 
4-14 + 
4-16± 
•07 
■07 
53-4 + 1 
53-7±l 
2 
0 
52-2+ -8 
52 -5 ±-6 
47 
46 
4 + 
6± 
■9 
•8 
25% 
> different 
crania 
TABLE III bis. 
English Crania, 50 Males. 
Series 
Meso- 
dacryal 
Chord 
(DC) 
Meso- 
dacryal 
arc (DA) 
Meso- 
dacryal 
Subtense 
ADS) 
Simotic 
Chord 
(SC) 
Simotic 
Subtense 
(SS) 
Meso- 
dacryal 
Index ji 
Meso- 
dacryal 
Index a' 
Meso- 
dacryal 
Index a 
Simotic 
Index S 
B ... 
C ... 
21-5+ -2 
21 -4± -2 
34-8+ -3 
34-6 ± -3 
12-1+ -1 
12-1 ± -1 
9-38+ -17 
9-43 ± -17 
4-68+ -10 
4-72± -10 
62-7 + 1-2 
62-7±l-2 
58-0+ -7 
58-1 ±-7 
56- 8+ -7 
57 - 4 ±-7 
50- 8+1-2 
51- 2 ±1-2 
A are measurements taken at start of investigation, B at conclusion of investigation after 
practise and standardisation, B only used in this memoir. In the Table III Us both series, B and 
C, were taken on the same crania at the end of the investigation with an interval of four months. 
* K. V. Byley, it is needless to say, had not her earlier values before her when making her 
remeasurements. 
Biometrika ix 51 
