28 BUREAU OF AMERICAN ETHNOLOGY IBITLL. 33 



Calaveras specimen must have great weight in favor of its cavern 

 origin. A mass of gravel, bones, etc., adhered to the base of the skull 

 when discovered, but this was not firmly solidified and could be 

 removed without injury to the bone. It had very much the appear 

 ance of debris from some cave or crevice, cemented to the specimen 

 while the latter was being coated with stalagmitic deposit. The infil 

 tration or fossilization of the Calaveras skull furnishes no reliable 

 test of its antiquity. It will be shown later in this paper that even 

 siliceous fossilization of bones can take place near the surface of the 

 ground, and in all probability has taken place within a geologically 

 insignificant period. The process is regulated wholly by the local 

 mineralogical conditions and the results are of little or no value as 

 chronological criteria. 



X. THE ROCK BLUFF CRANIUM 



The specimen known as the Rock Bluff skull was reported on by 

 Meigs, a Schmidt,^ and Kollmann, c and its claim to geological antiq 

 uity is based mainly on certain remarks found in Schmidt s account. 

 According to Meigs, the skull was found, with a lower jaw 



... in June, 1866, in a fissure of the rock, at Rock Bluff, on the Illinois river 

 where it is crossed by the fortieth parallel. The fissure, which is 3 feet wide, 

 was filled with the drift material of this region, consisting of clay, sand, and 

 broken stone, the whole being covered with a stratum of surface soil. In this 

 bed, which apparently had been undisturbed since the deposit, was found the 

 skull under consideration, at the depth of 3 feet. 



After giving a description of the specimen, which contains several 

 inaccuracies, Meigs speaks of a number of Indian crania which show 

 resemblances to that from Rock Bluff, and concludes as follows : 



Bearing in mind the locality in which it was found, the skull under considera 

 tion is so far unique in its ethnical character, that I do not feel authorized to 

 refer it to any of the aboriginal American cranial forms with which I am 

 acquainted. If the position in which it was discovered be any evidence of its 

 age, it belongs, in all probability, to an earlier inhabitant of the American con 

 tinent than the present race of Indians. 



At the time of Doctor Meigs s writing there was apparently extant 

 no important evidence of the geological antiquity of the find, and had 

 not the skull been of rather inferior type, it would hardly have 

 attracted particular attention. Four years later, however, Schmidt 

 gave a detailed description and measurements of the skull accom 

 panied by the statement that he was in possession of a letter from 



&quot; J. Aitken Meigs, Description of a Human Skull in the Collection of the Smithsonian 

 Institution, Smithsonian Report for 1867, 412-415, Washington, 1868. 



E. Schmidt, Zur Udgeschichte Xordamerikas, Arch f. Anttirop., v, 237-244, 1871-72, 

 c ,T. Kollmann, Holies Alter der Menschenrassen, Zcitschr. f. Ethnol., xvi, 191-193, 

 1884. 



