561: PROCEEDINGS OF SECTION F. 



On this subject Duckworth says {Morphology and Anthropology, 

 p. 372) : " There remains for notice a peculiar condition of the teeth 

 most frequently observed in natives of the Chatham Islands (Mori-ori) 

 and in Maories ; also, but less commonly, in Eskimo. The molar teeth 

 are dislocated and inflected inwards, so that instead of the normal 

 upper surface the labial side of the crown comes into use. The signifi- 

 cance and causation of the condition are quite obscure, but it would 

 appear to be related to the nature of the diet of the natives among 

 whom it obtains."* These remarks probably require to be revised. 

 Dr. Crank, of this city, informs me that the most extreme instances 

 he has seen have been in the white subject.f 



The relative sizes of the various molars, and the number of cusps 

 these teeth bear in different races, have formed the subject of extensi\fe 

 research in England, France, and Germany. Much of this has been 

 directed to Malays, Melanesians, and Polynesians, but the Australian 

 aboriginal has been, comparatively speaking, neglected in this particular. 

 The same requires to be said regarding the study of the shape of the 

 alveolar border of the jaws. 



Some remarks may be expected regarding the meaning of such 

 abnormalities of dentition as have been mentioned. To show what is 

 taught, and sometimes accepted, I may quote from a recent work on 

 dentistry. The author writes as follows {The American Text-hook of 

 Operative Dentistry, p. 50) : " Under the second head, Reversion to Primi- 

 tive Types, we have a variety of interesting phenomena in the form of 

 parts of the human teeth, which seem to be a zoological legacy. These 

 consist of conspicuous features which reappear and seem to recall 

 forms of the teeth observed in some of the lower animal orders, es- 

 pecially the quadrumana and insectivora. Among these featm-es may 

 be mentioned the curved upper central incisor, with the prominent 

 cingule on the Ungual-buccal ridge, making a notch which recalls the 

 incisors of the moles ; the prominent cingule on the lingual face of the 

 lateral incisor, which is not uncommon, and recalls the form found in 

 the insectivora and some of the quadrumana ; the extra-long, curved 

 canine, with extra-large median ridges, which recalls the large forms 

 of this tooth in the baboons and in the carnivora ; the double root 

 * sometimes found in this tooth is also a reversion to the insectivorous 

 type ; the three-rooted bicuspid is a quadrumanous reversion ; the 

 upper tricuspid molar is a primitive typal form, leading back to the 

 lemurs and beyond them to the early typal mammals found in fossil 

 formations ; the notched and grooved incisor recalls the divided in- 

 cisor of the Galeopithecus ; the double-rooted lower incisors and canines 



* This condition is referred to by Mummery in the communication mentioned 

 above, p. 36. 



t There are a good many examples of this condition in the South Australian 

 Museum collection of aboriginal skulls, and most, though not all, of the specimens 

 showing this pecuharity came from one locality near Adelaide. The condition 

 is often associated with abscess of the buccal roots. Some specimens in my 

 possession show that the lingual root remains in its normal position, while the 

 buccal roots project in such a way that their proximal portions fi^rm wide angle* 

 with the lingual root (Fig. 14).^ 



