46 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 83 



to be even more important than they had seemed to be hitherto. 

 Dr. Dubois told us he had about finished a final study of the speci- 

 mens, which was soon to be published. 



Later the same summer the specimens were shown also to Pro- 

 fessor McGregor, of Columbia University ; since then, they have 

 been demonstrated on a number of occasions, including that of the 

 XXI International Congress of Americanists at Hague, 1924, and 

 they have been studied in detail by Hans Weinert. 



DR. DUBOIS' LATEST I'LTRf-ICATIONS ON TIIK RF.^rATNS 



During that same year (1924), finally, there appeared in the Pro- 

 ceedings of the Academy of Sciences, Amsterdam, three new im- 

 portant publications on the Pithecanthropus remains by Dr. Dubois; 

 the first,' on the skull and brain with which the author now definitely 

 associates the fossil mandible, all three teeth and the thigh bone ; 

 the second' includes 11 excellent jjlates of the six^cimens ; and the 

 third * deals with the femur, and promises for the not far distant 

 future a final exhaustive work on the whole of the remains. 



In these latest and ripest communications on the Java remains are 

 found the following statements of special interest : 



STATE OF PRESERVATION AND AGE OF THE REMAINS 



The bones are in a "state of perfect mineralization" (p. 265). 

 Their specific gravity, like that of the Ixjnes of other mammals dug up 

 at Trinil, has risen to about 2.7. They contain only traces of organic 

 matter in the form of humus substances, " which give them a choco- 

 late-brown color." The skullcap " has been greatly corroded on the 

 outer surface by sulphuric acid, formed from pyrites in the volcanic 

 tufa " ; the femur (vol. 29, pp. 730-731) appears to be free from such 

 corrosions. 



The physical and chemical characters of the bones are such, in 

 Dubois' opinion, that they " stamp the remains of Pithecanthropus as 

 Pliocene " (p. 266) ; which possibility is further strengthened by the 



' Dubois, E., On the Principal Characters of the Cranium and the Brain, the 

 Mandible and the Teeth of Pithecanthropus ercctus. Proc. Acad. Sci., Amster- 

 dam, Vol. 27, Nos. 3 and 4, pp. 265-278, 1924. 



' , Figures of the Calvarium and Endocranial Cast, a Fragment of the 



Mandible and three Teeth of Pithecanthropus crectus. Ibid., Nos. 5 and 6, 

 pp. 459-464- 



' , On the Principal Characters of the Femur of Pithecanthropus erectus. 



Ibid., Vol. 2y, No. 5, pp. 730-743, 1926. 



