The anterior basal length (basion-nasion) is a measurement of importance, though its full meaning in anthropology is not yet entirely clear. From data quoted by Martin (Lehrb., 715-716) it appears to average in whites up to 10.3 centimeters in males and up to 10.1 centimeters in females, and is known to correlate closely with the length of the vault. Secondarily it also correlates with stature. Data on American Indians are not yet generally available, though in preparation. The Munsee skulls gave the writer for the diameter the means of 10.27 for the males and 10.02 for the females; the mound skulls from Arkansas and Louisiana gave 10.45 for the males and 9.77 for the females. An abstract of the data on the Eskimo skulls is given in the next table. The values for the measurement are rather high, especially for such short people. The percentage relation of the measurement to the length of the skull appears also to be high. Manouvrier (1882, quoted in Martin, Lehrb., 716) found this relation in French skulls to be _53.6_ in the males and _54.7_ in the females. ESKIMO CRANIA: BASION-NASION LENGTH ---------------------------------+-------------------+------------------- | Groups of males | Corresponding | | groups of females +--------+----------+--------+---------- | | Its | | Its | Basion-|percentage| Basion-|percentage | nasion | relation | nasion | relation |diameter|to length |diameter|to length | | of skull | | of skull ---------------------------------+--------+----------+--------+---------- | (13) | (13) | (13) | (13) Southwestern and Midwestern | 10.38 | _56.4_ | 9.85 | _55.7_ | (6) | (6) | (6) | (6) Northwestern | 10.58 | _56.4_ | 10.06 | _56.3_ | (5) | (5) | (5) | (5) Northern Arctic and northeastern | 10.65 | _56.2_ | 10.06 | _55.4_ ---------------------------------+--------+----------+--------+---------- The female measurement to that of the male, in the Eskimo, is as _94.9_ to 100. As a similar relation of the cranial modules in the two sexes is close to _95.7_, the anterior basal length would seem to be at a little disadvantage in the female Eskimo skull.