In conclusion, therefore, we may say that the remains of Pithecanthropus are so scanty, fragmentary, and doubtful, as to preclude a reliable verdict on their true significance. As Virchow pointed out, the determination of their correct taxonomic position is impossible, in the absence of a complete skeleton. Meanwhile, the most probable opinion is that they represent the remains of a giant ape of the hylobatic type. In other words, the Pithecanthropus belongs to the genealogical tree of the apes, and not to that of man. In fact, he has been excluded from the direct line of human descent by Schwalbe, Alsberg, Kollmann, Haacke, Hubrecht, Klaatsch, and all the foremost protagonists of the theory of collateral descent. (Cf. Dwight, _op. cit._, ch. VIII.) Professor McGregor’s series consisting of an ape, the Pithecanthropus, Homo neanderthalensis, and the Crô-Magnon Man fails as an argument, not only for the general reason we have discussed in our third chapter, but also for two special reasons, namely: (1) that he completely ignores the chronological question of the comparative age of the fossils in his series, and (2) that he has neglected to take into account the consideration of the body-brain ratio. For as Prof. G. Grant MacCurdy puts it, “We must distinguish between relative (cranial) capacity and absolute capacity.” (Smithson. Inst. Rpt. for 1909, p. 575.) In justice to Professor McGregor, however, it should be noted that he proposes his interpretation in a purely provisory and tentative sense, and does not dogmatize after the fashion of Osborn and Gregory.