Note 3 — Subfamily I. BUBALIDINÆ.

These three measurements, when obtainable, will be given of the skull of every species throughout the work. The “basal length” is taken from the front lower edge of the large hole at the back of the skull, the foramen magnum, to the front of the muzzle, in a straight line; the other two explain themselves. The fourth and fifth measurements are only given in this genus to show the development of the frontal elongation.