CRANIAL CAPACITY, PROJECTION MEASUREMENTS. 



2? 



Of the 17 males measured, the capacity varied from 1255 cc. to 1650 cc, average, 

 1404.4 cc. ; of the 18 females measured, the extremes ranged from iioo cc. to 1600 cc, 

 the average, 1287.5 cc. 



TABLE XXIV. 



Cranial Capacity. 



New England Indians. 



PROJECTION MEASUREMENTS. 



Whenever possible, the skull was clamped into a "Kubus Kraniophor" adjusted to the 

 Frankfort horizontal ; and a tracing of the sagittal curve made by the use of a Lissauer 

 diagraph (made by P. Hermann, Zurich). The median points on this curve, opisthion, 

 inion, lambda, bregma, nasion, prosthion, basion, were carefully marked by pricking the 

 paper under the lead of the diagraph pencil at these points. 



The calvarial height, the lenglh of the perpendicular from the nasion-inion line to the 

 highest point on the curve, varies, in the male, from 98 mm. to 115 mm.; in the female, 

 from loi mm. to 114 mm. 



Schwalbe used at first the glabella-inion as the base upon which to erect the calvarial 

 height but the nasion-inion is now considered more practical, as in many cases, especially 

 in female skulls, the glabella is not noticeably projecting. 



The amount of curvature of the frontal bone, which is correlated with a greater or less 

 development of the frontal lobes of the brain, 'can be accurately measured by the size of 

 the angle whose apex is on the frontal arc, at the base of the perpendicular from the 

 frontal chord to the highest point of the arc, and whose arms pass through nasion and 

 bregma. As the value of the angle approaches 180° the frontal arc approaches its chord, 

 thus signifying a less development of the frontal lobes ; conversely as the value of the angle 

 approaches 90°, the size of the frontal arc increases, thus denoting a greater development 

 of the frontal lobes and presumably a higher state of mental growth. 



This frontal curvature angle varies, in the male, from 127° to 144°; in the female, from 

 122° to 138°. The females show on the whole a tendency toward a smaller angle than 

 the males. 



