282 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1918. 



was found to be a true cave deposit, presenting a small exposure, or 

 outcrop, at the base of the almost perpendicular southern wall of the 

 cut which at this point is about. 100 feet deep. 1 



This preliminary examination revealed the fact that, while great 

 quantities of the bone-bearing material had been blasted out and 

 carried away by the steam shovel, there still remained a considerable 

 mass which had not been disturbed and which promised to be well 

 worth a thorough exploration. Following the report of conditions 

 and prospects to the museum authorities, a systematic excavation 

 for the careful collecting of the fossil bones was undertaken. The 

 deposit proved to be of considerable depth and extent, and very 

 rich both in quantity and quality of fossils, which were exceedingly 

 varied in kinds of animals represented. 



The work, begun in the spring of 1912, proceeded at intervals as 

 the limited available funds permitted, and was not completed until 

 the spring of 1915. A preliminary report of the results of the first 

 two expeditions was published in August, 1913. 2 At this time there 

 had been recognized in the collection, 29 species distributed among 

 6 orders of mammals. The work of the following two years yielded 

 many more specimens, and among them were the best obtained at 

 this locality. Incidentally these also added many new species to the 

 list reported in 1913, so that the list now includes no less than 45 

 distinct species or kinds of mammals referable to seven different 

 orders. To these may be added a few species of reptiles, including 

 two snakes, and a species of alligator or crocodile. The actual 

 identity of the latter is not certain, since it is represented by only a 

 single tooth. 



The mammals represented constitute a varied and, in some respects, 

 strange assemblage. They range in size from a bat smaller than 

 a house mouse to a mastodon which attained the size of an elephant. 

 Probably none of these except the bats could properly be called 

 cave living animals. Most of the species are now extinct, although 

 many of the extinct forms belong to present day genera, 3 and doubt- 

 less very closely resembled their living relatives. Among those 

 animals referable to living genera are bats, shrews, squirrels, porcu- 

 pines, ground hogs or woodchucks, field or pocket mice, wood rats, 

 beavers, rabbits and picas, bears, wolves, lynx, wolverines, badgers, 



1 The accompanying figure, pi. 2, presents a view of the focation and immediate sur- 

 roundings of this cave deposit as it appeared after a great part of the subsequent exca- 

 vating had been completed. It will be noted that here the rock ledges or strata have 

 been tilted up by mountain folding to a degree at which they are standing almost directly 

 on edge. A faint trace of peculiar weathering leading almost directly upward to the 

 summit of the cliff evidently indicates the original opening of the cavern to the surface of 

 the ground before the railroad cut was made. 



2 Gidley: Proc. U.S.N.M., vol. 46 (1914), No. 2014, 1913, pp. 93-102. 



3 A genus is a natural group or assemblage of species having certain distinguishing 

 characters in common. For example the genus Canis includes all the species or kinds of 

 true wolves and dogs. 



