36 



SMITHSONIAN INSTITUTION 



How did these bones get into such a place, back in this black dark- 

 ness more than a half mile from the nearest known entrance? And 

 to what age did they belong ? These are questions at first not easy to 

 answer. Mr. Perry's first impressions had been that they were bones 

 of animals that, having fallen into or taken refuge in the opening, 

 had been washed by former stream currents or dragged by other 

 animals back into the far recesses of the cave. But later investi- 

 gation revealed the fact that most of the larger bones were broken 

 and that all were more or less scattered about and mixed with the 

 broken debris of the fallen roof. This would not have l)een the case 



Fig. 27. — Opening to lava cave about 15 miles south-southwest of Bend, 



Oregon. 



had the carcasses been transported there before maceration of the 

 fleshy parts had taken place. If, however, it is assumed that the bones 

 of animals living in the country over these caverns should from time 

 to time have fallen into cracks and crevices of the lava covering, they 

 might readily work their way downward by shifting and slight earth 

 movements until, aided by this cave-in. some of them found a more 

 permanent resting place at the bottom of the cavern among the fallen 

 debris of the roof. Careful search with our lanterns revealed that 

 there were such crevices in the irregular broken vault of this portion 

 of the cavern. The animals represented in the small collection which 

 included an extinct species of horse and a large hyena-like dog, 

 indicated that they were not recent forms but belonged to the last 

 geologic period just preceding our own time, the Pleistocene. 



