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University of California Publications in Geology [Vol.7 



teeth of the captor. The suggestion is also made that the cavern 

 may have been used as a den for hibernation by various ursines, 

 even as other caverns in the region are known to be used by 

 bears of today. 



No specimen of bird skeleton was found with bones in proper 

 place, so the probability is that the remains representing this 

 class were introduced largely as in the case of the Potter Creek 

 Cave specimens. Some essential difference must have existed, 

 however, since the relation in numbers of the different species is 

 so different in the two localities.' The Cathartiformes appear in 

 Potter Creek Cave represented by forty-five specimens distri- 

 buted over three species. In Samwel Cave there appear but six 

 specimens possibly assignable to the group. Falco peregrinus, 

 represented in the former cave by four specimens, is wanting in 

 the latter. The owls are represented by five specimens in the 

 former and eleven in the latter, the grouse by thirty-four in 

 the former as against one hundred and twenty-four in the 

 latter. 



This difference of faunal proportions is perhaps most readily 

 explained by the probable difference between the original open- 

 ings of the caves. Let it be conceded that, as suggested by the 

 respective authors, Potter Creek Cave opened by a relatively 

 small chimney or two on the surface of the Pleistocene hillside 

 and that Samwel Cave opened by a large chamber, the first part 

 of which ran more nearly horizontally. Vultures, ravens, and the 

 peregrine falcon nest in small cavities in rocky cliffs out of the 

 way of small predatory mammals like the raccoons and the 

 weasels. Their bones and those of their prey would accumulate 

 in these pockets and eventually find their way into deeper re- 

 cesses through fissures or chutes as described by Sinclair. The 

 owls, however, resort to large open-mouthed caves to roost during 

 much of the year, which fact would account for their greater 

 abundance in Samwel Cave. Raccoons were found in abundance 

 by Furlong as entire skeletons on the floor of Samwel Cave, thus 

 suggesting that these animals frequented the place as a lair. 

 The ground-dwelling birds, their natural prey, thus come to 

 form a large proportion of the avian remains in these deposits. 

 Procyonid forms are not listed by Sinclair from Potter Creek 



