[Vectorial description of the horizontal craniogram].

After the polynomial approximation we used Bezier's algorithm to obtain a vectorial description and to compare the horizontal craniogram morphology of hominid skulls. A minimum number of determinant points chosen on the original curves constitutes the vertices of a closed polygonal. By these points Bezier's interpolation gives new curves very similar to the polynomial curves obtained by the original ones. Each pair of consecutive segments was used to construct a parallelogram and so to have a vector. We applied the procedure on horizontal craniograms of Sts V. Pithecanthropus (erectus) VIII (Sartono), Circeo I (after S. Sergi) and a modern human female skull. Ten vectors for each skull were detected and compared. Some similarities in frontal and posterior regions of P VIII and Circeo I were explained in terms of common morphological solution to the problem of mechanical stability in the skulls with pronounced platycrany under chewing load.