The cry of victory may be raised a little too soon. It may be hard to find the correct method, without being necessarily impossible. The “unitarians,” however, do not admit this reservation. They support their view by observing that certain tribes that belong to the same race show a very different physical type. They cite, for instance, the various branches of the hybrid Malayo-Polynesian family, without taking account of the proportion in which the elements are mingled in each case. If groups (they say) with a common origin can show quite a different conformation of features and skull, the unity of the human race cannot be disproved along these lines at all. However foreign the negro or Mongol type may appear to European eyes, this is no evidence of their different origin; the reasons why the human families have diverged will be found nearer to hand, and we may regard these physiological deviations merely as the result of certain local causes acting for a definite period of time.[56] In face of so many objections, good and bad, the champions of multiplicity tried to extend the sphere of their arguments. Relying no longer on the mere study of skulls, they passed to that of the individual man as a whole. In order to prove (as is quite true) that the differences do not merely lie in the facial appearance and the bony conformation of the head, they brought forward other important differences with regard to the shape of the pelvis, the proportions of the limbs, the colour of the skin, and the nature of the capillary system. Camper and other anthropologists had already recognized that the pelvis of the negro showed certain peculiarities. Dr. Vrolik pushed these inquiries further, and observed that the difference between the male and female pelvis was far less marked in the European, while in the negro race he saw in the pelvis of both sexes a considerable approximation to the brute. Assuming that the configuration of the pelvis necessarily affected that of the embryo, he inferred a difference of origin.[57] Weber attacked this theory, with little result. He had to recognize that some formations of the pelvis were found in one race more frequently than in another; and all he could do was to show that there were some exceptions to Vrolik’s rule, and that certain American, African, and Mongolian specimens showed formations that were usually confined to Europeans. This does not prove very much, especially as, in speaking of these exceptions, Weber does not seem to have inquired whether the peculiar configuration in question might not result from a mixture of blood.