Two new statistical tests are presented which were developed for studying morphological trends in hominid evolution. The first test is concerned with the null-hypothesis that population mean vectors are situated on a straight line, indicating morphological change into one direction. The second test, which is an extension of the first, is concerned with the null-hypothesis that two or more of such lines are parallel, indicating morphological change into the same direction of two or more hominid lineages. Some preliminary results, obtained with cranial measurements of groups of later hominids, are given.