308 ANTHROPOLOGICAL SURVEY IN ALASKA [eth. axn. 40 



and Pain 21 report the " thickening " in 10 out of 32 Eskimo jaws, 

 but do not discuss the causation ; and the same applies to Oetteking, 23 

 who reported on a series of Eskimo from Labrador. In 1909 

 Gorjanovie-Kramberger 23 somewhat indirectly notes the condition, 

 without a true appreciation of its meaning. 



In 1910 I had the opportunity to report on the mandibular hyper- 

 ostoses in a rare collection of crania and lower jaws of the central 

 and Smith Sound Eskimo. 24 Of 25 lower jaws of adults and 5 of 

 children, 18, or 72 per cent, of the former and 2 of the latter showed 

 distinct to marked lingual hyperostoses, while in the remaining cases 

 the feature was either doubtful (absorption of the alveolar process) 

 or absent. Two of the five children showed the peculiarity in a 

 well-marked degree. A critical consideration of the condition leads 

 me to the conclusion that it is not pathological, and my remarks 

 were worded (p. 211) as follows: "A marked and general feature 

 is a pronounced bony reinforcement of the alveolar arch extending 

 above the mylohyoid line from the canines or first bicuspids to or 

 near the last molars. This physiological hyperostosis presents more 

 or less irregular surface and is undoubtedly of functional origin, the 

 result of extraordinary pressure along the line of teeth most con- 

 cerned in chewing; yet its occurrence in infant skulls indicates that 

 at least to some extent the feature is already hereditary in these 

 Eskimo." 



In 1912, Kajava 25 reported lingual hyperostotic thickenings on the 

 lower jaws of 68 adult Lapps, and found the condition in frequent 

 association with pronounced wear of the teeth. In 1915, finally, 

 Fiirst and C. C. Hansen, in their great volume on " Crania Groen- 

 landica," approach this question much more thoroughly. They, as 

 also Kajava, did not know the writer's report of 1910. They found 

 the " torus " (p. 181) , " also in the mandibles of some various Siberian 

 races in a not insignificant percentage * * * and also not in- 

 frequently among European races, especially in the Laplanders 

 (30 to 35 per cent)." They also report the presence of the condi- 

 tion " in a Chinaman," and saw indications of a good development 

 of it in 17 per cent of 164 middle ages to prehistoric, and in 12 per 

 cent of later Scandinavian lower jaws. Their interesting comments 

 on its possible causation, though at one point seemingly not har- 

 monizing, are as follows (p. 180) : " The possibility is not precluded 

 that we have here a formation which, even though it has at first 

 arisen and been acquired through mechanical causes, has in the end 



^ J. Anthr. Inst. 1900, xxx. 134. 



22 Abh. und Ber. Zool. und Anthr. Mus., Dresden, 1908, XII. 



a Sitzbcr. preuss. Ak. Wiss., M— Lin. 



M Anthrop. Pap's. Am. Mus. Nat. Hist., v, pt. II. 



■" Verb.. Ges. Finn. Zahnarzte, 1912, ix. 



