Fig. 36. Profile of the skull of Pithecanthropus, as restored by J. H. McGregor. 1914. One-third life size.
This prehuman stage has, none the less, a very great significance in the developmental history of man. In our opinion it is the very stage which, theoretically, we should anticipate finding in the dawn of the Pleistocene. A similar view is taken by Büchner,[(24)] who presents in an admirable diagram (Fig. 117) the result of his comparison of twelve different characters in the skulls of Pithecanthropus, the Neanderthals, the Australians, and the Tasmanians. One of the main objects of Büchner's research was a very detailed comparison of the Trinil skull with that of the lowly and now extinct Tasmanian race, which, we observe in the diagram, occupies a position only a little higher than that of the Spy-Neanderthal race.
Fig. 37. Three views of the skull of Pithecanthropus, as restored by J. H. McGregor, showing the original (shaded) and restored (black lines) portions. About one-quarter life size.
If the femur belongs with the skull, the Trinils were a tall race, reaching a height of 5 feet 7 inches as compared with 5 feet 3 inches in the Neanderthals. The thigh-bone (Fig. 122) has a very slight curvature as compared with that of any of the apes or lemurs, and in this respect is more human; it is remarkably elongate (455 mm.), surpassing that of the Neanderthals; the shin-bone (tibia) was probably correspondingly short. The two upper grinding-teeth preserved are much more human than those of the gibbon, but they do not resemble those of man closely enough to positively confirm the prehuman theory. Dubois observes:[(25)] "That the tooth belongs to some hominid form needs no further demonstration. Aside from its size and the greater roughness of the grinding surface, it differs from the human grinder in that the less developed cusp of Pithecanthropus is the posterior cusp next the cheek, while in man it is generally the posterior cusp next the tongue. The simplification of the crown and the root of the Trinil grinder is quite as extensive as it usually is in man."
Fig. 38. Profile view of the head of Pithecanthropus, the Java ape-man, after a model by J. H. McGregor. One-quarter life size.
Various efforts have been made to supplement the scattered and scanty materials collected by Dubois. The Selenka expedition of 1907-8 brought back a human left lower molar as the only result of an express search for more Pithecanthropus remains. Dubois is also said to possess the fragment of a primitive-looking lower jaw from the range known as the Kendeng Hills, at the southern base of which lies the village of Trinil.
It remains for us to consider the stage of psychic evolution attained by the Trinil race, and this naturally turns upon the erect attitude and what little is known of the size and proportions of the brain.
