HRDLICKA] 



SKELETAL REMAINS 



27 



The measurements of both specimens which could be secured exactly 

 or with a close degree of approximation are as follows : 



&quot; Approximate. 



The thickness of the frontal bone could not be measured in the cave 

 skull on account of the stalagrnitic deposit inside, but it is apparently 

 very nearly the same as that in the Calaveras specimen. 



The measurements show a somewhat smaller frontal bone in no. 

 225172, which probably indicates that the Calaveras skull as a whole 

 was larger. At all events such differences are not outside of the scope 

 of individual variation within a single people. The remaining meas 

 urements, particularly the important nasal and orbital indexes, are so 

 much alike that on the basis of these and of the other resemblances it 

 is impossible to do otherwise than to pronounce the two specimens of 

 the same type, which necessarily leads to the implication that the 

 Calaveras skull is geologically recent. 



There is one feature connected with the Calaveras skull besides the 

 scarcity of secondary injuries which may not have received the con 

 sideration it deserves ; this is its calcareous coating, which, though col 

 ored on the surface, is white and crystalline on fracture, exactly like 

 that of the cave skulls. How could such a coating have been formed, 

 and formed with much uniformity, over the surfaces of a skull packed 

 in sand or mud and gravel of an ancient river? It is probable that, 

 under special circumstances, bones manifest some affinity for calcare 

 ous matter in solution, and it is known that animal fossils with some 

 what similar coating have been recovered from ancient sands or grav 

 els. This phenomenon is most commonly observed in caves or crevices 

 into which water percolates, carrying lime in solution, and, in view of 

 the presence of numerous such caves and crevices in the Calaveras 

 region, the occurrence of typical cavern deposits on the surfaces of the 



