Average height 1.486 Range 1.440 to 1.530 " length of head .182 .171 to .191 " breadth of head .143 .136 to .150 " bizygomatic width .131 .127 to .136 " length of nose .037 .033 to .042 " width of nose .037 .036 to .038 " cephalic index 78.59 nasal index 99.7 From these descriptive sheets it is obvious that each tribe is made up of very heterogeneous elements, and each overlaps the other to a considerable extent; however, the number of individuals measured is sufficiently great for us to draw certain general conclusions from the averages of each group. It is at once evident that the differences between the Ilocano and the Valley Tinguian are very slight, in fact are less than those between the valley and mountain people of the latter tribe. The Ilocano appear to be slightly taller, the length of head a little less, and the breadth a bit more; yet there is an average difference of only two points in the cephalic indices of the two groups. The only other points of divergence are: the greater percentage among the Ilocano of eyes showing the Mongolian fold, and the occurrence of straight hair in about half the individuals measured. However, this latter feature may be more apparent than real; for the Ilocano cut the hair short, and a slight degree of waviness might readily pass unobserved. As we pass from the Valley to the Mountain Tinguian, and from them to the Apayao, we find the average stature almost constant, but the head becomes longer; there is a greater tendency for the cheekbones to protrude and the face to be angular, and there is a more frequent development of the supra-orbital ridges. The root of the nose is often flat and the bridge concave; while wavy hair becomes the rule in the mountains. There is a slight decrease, in the Tinguian groups, of eyes showing the Mongolian fold, but in the Apayao the percentage again equals that of the Ilocano. The Apayao present no radical differences to the Mountain Tinguian; yet, as already noted, the length and height of the head are slightly greater; the zygomatic arches more strongly developed; the face more angular; and the nose is broader as compared with its length. Evidences of former extensive intermixture are here apparent, while at the present time there is rather free marriage with the neighboring Kalinga and Negrito.