GENETIC TYPE AND THE ENDOCRINES 163 



zygomatic width and the interorbital width and brings about 

 an accord between these two measurements. Wide inter- 

 pupillary distance and wide cheek bones are also thus cor- 

 related in the heads of human racial types. 



In the third place, the last five groups of measurements, 

 made entirely on the facial skeleton, all agree in general 

 with the zygomatic width series, yet even these show strong- 

 individual discords which are due more largely to type than 

 to size differences among the skulls. The zygomatic width 

 is definitely a facial measurement quite unrelated to cranial 

 width. Disproportionately wide zygomatic arches are as- 

 sociated with short, wide facial skeletons, and thus the total 

 skull sizes do not show strict accord in series with zygomatic 

 widths. 



A comparison of widths at different cranial regions. A 

 second series of measurements was made in order to deter- 

 mine whether the widths across three different regions of the 

 cranium showed a close correlation. In other words, if a 

 cranium is broad in the posterior region, is it also wide in 

 the anterior region? To determine this, the seventy skulls 

 were arranged in a graded sequence from widest to narrowest 

 according to the individual cranial width (pi. 35, fig. 1, G). 

 This arrangement is represented in text-figure 11, and a gentle 

 and quite regular slope from a width of 65 mm down to 45 mm 

 is shown. The difference between the narrowest and widest 

 crania is only as 1.44:1. 



When the measurements for the least frontal widths (pi. 

 35, fig. 1, E) are plotted in the same sequence, the chart 

 shown as text-figure 12 results. These widths range from 

 49 mm down to 27 mm, the greatest and least differing from 

 one another about as 1.75:1. A curve drawn along the tops 

 of the lines in this figure shows that no relation whatever 

 exists between this curve and the one for cranial widths, in 

 which the same skulls are in identical sequence. It is sur- 

 prising to find that in the crania of the different dog breeds 

 there is no correlation between cranial widths and least 



