to the Anthropology of the Sudan. 145

Table I.

The following are the chief data for those tribes of which more than five individuals were measured :—

Tribe. No. Head Length.

Head Breadth.

Auricular

Vertical

Radius.

Horizontal

Circum¬ ference.

Cephalic

Index.

Nasal Index.

Radio- gnathic

Index.

Upper

Facial Index.

Dinka 17 191-06 138-70 145-83 538*71 72-71 98-99 111-27 46-23

(6-92) (5-47) (3-95) (16-75) (3-58) (8-53) (3-44) (2-71)

— — — — ± 0-59 ± 1-40 — ± 0*44

Shilluk ... 11 193-40 138-54 141-40 548-30 71-70 93-32 110-96 4712

(4-71) (4-14) (2-15) (11-20) (2-93) (8-95) (3-27) (2-39)

— — — — ± 0-60 ± 1-82 ± 0-98 =b 0-49

Nubawi ... 20 189-15 143-90 142-30 535-00 76-18 101-18 109-89 45-68

(6-40) (5-64) (5-37) (13-60) (4-19) (5-89) (4-32) (2-40)

— — — — ± 0-61 ± 0-89 ± 0-84 ± 0-36

Tagalawi 7 186-00 147-00 142-00 545-75 79-06 103-21 107-15 44-41

(6-21) (4-81) (5*90) (11-34) (1-63) — — —

— — — — ± 0*42 — — —

Furawi ... 18 190-70 141-94 140-18 541-60 74-39 102*63 109-90 45-10

(3-40) (4-48) (3-08) (9-36) (3-09) (7-68) (4-60) (1'88)

— — — — ± 0-49 ± 1-22 ± 0-90 ± 0-30

Bertawi ... 8 186-38 141-37 138-00 529-00 75-86 101-29 107*03 46-14

(5-60) (3-57) (2-24) (2-15) (3-13) — — —

• — — — — ± 0-74 — —

The figures in the second column give the number of individuals measured in each tribe ; those in the following columns give the mean values for the various measurements ; the figures in brackets express the standard deviations1 of the means, and those preceded by the sign + show the probable errors2 of the means.

1 The standard deviation (tr) is obtained from the expression a —

the number of individual measurements and 2 §2 is the sum of the squares of the differences of individual measurements from the mean.

2 The probable error (p.e.) is found from the expression p.e. = 0'6745 f_ . Unfortu- v n nately the number of individual measurements is often so small that this constant cannot be satisfactorily calculated.

h

v

2 82 where n is n