WHOLE VOL. SKELETAL REMAINS OF EARLY MAN HRDLICKA 35 1 



scribed in the American Journal of Physical Anthropology. The 

 greatest former difficulty with measurements of teeth, particularly 

 the molars, was that while some of the teeth were loose, others were 

 still in position in the jaws. Now on a loose molar, particularly one 

 from the lower jaw, it is relatively easy to secure the maximum length 

 and breadth as well as other dimensions ; but on the same tooth when 

 in position and close contact with the neighboring teeth, accurate 

 measurement of the maximum length is often difficult if not im- 

 possible. A few trials in this direction will soon convince the student 

 of this fact. The difficulties are due to the frequently irregular contour 

 of the teeth and to the greater or lesser bulging of the enamel below, 

 the upper border of the crown, which cannot be reached by the 

 instrument when the teeth are in close apposition. If we add to this 

 the fact that the maximum lengths of the three molars measured 

 separately give, in many instances, a greater total length than that 

 of the three teeth measured as a whole, the desirability of seeking 

 the maximum length of the crown becomes questionable. 



The method arrived at by the writer was to measure the length 

 of the molars along their median antero-posterior axis, in other words 

 along the middle of the crown, from articulation (or contact) to 

 articulation if the tooth is still in the jaw, or from the middle of the 

 upper border of the articular facet anteriorly to a similar point of 

 a similar facet posteriorly, if the teeth are loose. Even this method 

 encounters some difficulties due to occasional notching of the anterior 

 border of the tooth, or an absence or unusual position of the facets, 

 but on the whole it has proved easier and more satisfactory than the 

 measurement of length maximum. With the breadth there are no 

 such difficulties. All observers, it seems, take the greatest breadth 

 of the tooth, and the measurement may be safely defined as the 

 greatest breadth of the crown at right angles to the length as well 

 as to the vertical (mid-crown-mid-root) diameter of the tooth. 



The principles of the method having been settled, the next point 

 was that of instruments. It was soon seen that the ordinary coinf^as 

 d'epmsseur, though accurate enough for other purposes and though 

 its blunt branches are very useful for the measurement of the maxi- 

 mum breadth of the teeth, was not entirely satisfactory for measur- 

 ing the tooth length. The best instrument for the latter measurement 

 was found to be a pair of sharp-pointed calipers, supplemented by a 

 magnifying glass. The practice develoi^id therefore of taking the 

 length of the tooth by the sharp pointed compass under a magnifying 

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