680 THE POPULAR SCIENCE MONTHLY. 



most likely to meet with, at least a few specimens of a character 

 to which reference has just been made. 



These fossils were principally of water birds, having been dis- 

 covered in the former bottoms of dried-up Tertiary alkali lakes, 

 or upon the margins of those undergoing a similar process. With 

 them were found immense numbers of arrow points of human 

 manufacture, and the question had arisen as to whether it were 

 not possible that they had been shot at the game during former 

 times. To shed further light upon such an interesting subject, I 

 most carefully examined each and all the specimens to discover if 

 possible any healed wounds (fossilized) that may have been pro- 

 duced by such means. My interest in this matter was much 

 stimulated by what Prof. Cope had formerly written in the 

 American Naturalist for November, 1889. After describing the 

 discovery of the bird-fossils referred to above, that eminent pa- 

 leontologist there says that "scattered everywhere in the de- 

 posit were the obsidian implements of human manufacture. Some 

 of these were, of inferior, others of superior workmanship, and 

 many of them were covered with a patine of no great thickness, 

 which completely replaced the natural luster of the surface. 

 Other specimens were as bright as when first made. The abun- 

 dance of these flints was remarkable, and suggested that they had 

 been shot at the game, both winged and otherwise, that had in 

 former times frequented the lake. Their general absence from 

 the soil of the surrounding region added strength to this supposi- 

 tion. Of course, it was impossible to prove the contemporaneity 

 of the flints with animals with whose bones they were mingled, 

 under the circumstances of the mobility of the stratum in which 

 they all occurred. But had they been other than human flints, 

 no question as to their contemporaneity would have arisen " (page 

 979). 



Now, I found no fossilized injuries of the bones in question 

 that could be attributed to wounds of them that arose from ar- 

 row-shot ; but, on the other hand, one or two pathological condi- 

 tions of interest were discovered, and one of these a fracture in 

 the course of healing. 



In order to make clear the stage at which this healing frac- 

 ture existed at the time of the death of the individual that sus- 

 tained it, I will first offer a few remarks upon the course of such 

 injuries in existing animals. 



Fractured extremities of bones in both mammals (not includ- 

 ing man) and birds are rarely kept quiet and properly approxi- 

 mated during the healing process, which takes place at the 

 fractured extremities. This results in the formation of a " pro- 

 visional callus" which soon surrounds the broken ends of the 

 bones, and acts as an osseous splint, that strengthens with time. 



