486 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.40. 



tektites from various sources are so wholly unlike that it is impossible 

 to conceive of their having a common origin, or been formed through 

 the same agencies, and above all it is to be noted that in no case do 

 they resemble the flutings which are characteristic of known meteor- 

 ites. This, it seems to me, can not be accounted for on the ground 

 of their superior refractibility, but as rather indicating an entirely 

 different origin. Further than this again, the smaller meteoric 

 stones, those corresponding in size with the tektites, rarely if ever show 

 pittings and flutings. It is only the larger forms apparently which 

 hold their orientation for a sufficient length of time for flutings to de- 

 velop. The smaller forms are mere rounded blebs as is abundantly 

 illustrated by the hundreds of individuals constituting the Pultusk 

 and other noted falls. I can not, therefore, at all agree with Suess 

 in his conclusions on this branch of the subject. Whatever may 

 have been their original source, the Bohemian and Moravian speci- 

 mens are now simply water-worn pebbles of weathered glass, origi- 

 nally etched by corroding vapors or solutions, the results being indis- 

 tinguishable from those produced by artificial etchings on obsidian 

 with fluorhydric acid. The Australian forms are likewise, to me, 

 simply pebbles of glass which have been water worn or abraded by 

 wind-blown sands. In their contours there is nothing even suggestive 

 of meteoric markings, nor do I find any semblance of such an origin 

 so far as the surface markings alone are concerned in the examples 

 from Billiton. I do not, however, agree with Dr. G. F. Kunz J in 

 regarding the pittings as due to "large bubble cavities that have 

 been broken into by attrition.'' 



In the above, it will be noted, I do not attempt or wish to con- 

 trovert the theory of a cosmic origin for these very remarkable and 

 interesting bodies. Until, however, such shall be seen to fall, it 

 would seem that the explanation of their source or origin is to be 

 found only in the conditions under which they occur and their some- 

 what anomalous composition. 



EXPLANATION OF PLATES. 



Plate 61. 



i 



Figs. 1 to 3. — Billitonites from the island of Billiton. 

 4 to 6. Moldavites from Moldavia and Bohemia. 

 7 to 9. Australites and an Obsidian button from Australia. 



Plate 62. 



Figs. 1 and 2. Moldavite-like Obsidian pebbles from Cali, in Colombia, South America. 

 Fig. 3. Obsidian pebble from Clifton, Arizona. 



4. Obsidian pebble from near Marsh, Idaho. 



5. Obsidian pebble from High Rock Canyon, Nevada. 



6. Obsidian from Obsidian flow near Myvatu, Iceland. 

 7-9. Obsidian pebbles etched by fluorhydric acid. 



1 Twentieth Ann. Rep. U. S. Geol. Surv., part 6, p. 594. 



