6 BULLETIN 171, UNITED STATES NATIONAL MUSEUM 



ENVIRONMENT OF THE FAUNA 



Evidence of the environmental conditions- that prevailed m the 

 region of the cave during the time in which the fossil material accinnu- 

 lated might reasonably be expected from a consideration of the various 

 forms present in the fauna. Many of the species recognized are 

 closely related to living forms, and it seems probable that their habits 

 were not greatly different from those of living representatives. 



The fauna from the cave includes a peculiar assemblage of animals. 

 Many of the species are comparable to forms now living in the vicinity 

 of the cave, but others are distinctly northern, or Boreal, in their 

 affinities and some are related to species peculiar to the southern, or 

 Lower Austral, region. The fauna now living in this part of Maryland 

 is composed principally of species representative of the Carolinian or 

 Upper Austral region and of the Alleghenian division of the Transition 

 Zone (xMerriam, 1900, p. 292). 



The wolverine, Gulo, and lemmings of the group Miciomys are 

 distinctly northern in range, and it seems highly improbable tliat they 

 were contemporaneous in the same region with a crocod^did and a 

 tapir. Such an association might be plausible with sufficient topo- 

 graphic relief, but from a consideration of the physiographic history 

 it seems evident that during the time in which the cave deposit 

 accumulated relief was not greater than at present, as streams may 

 not liave cut so deeply bek)w the old upland surfaces. A more 

 probable explanation of the apparent association is that the fauna is 

 not entirely contemporaneous and that the entombment extended 

 over a period of time sufficient to allow important climatic changes to 

 take place. The cave may have received material during a portion 

 of a glacial and of an interglacial stage. Gidley (1920a) contended 

 that the forms were contemporaneous in the same region, postulating 

 greater relief, but the physiographic evidence does not seem to 

 justify his reasoning. 



Included among the forms that may well have been associated 

 with wolverine and lemming mice in the colder famui are the long- 

 tailed shrew, fisher, mink, red squirrel, muskrat, porcupine, jumping 

 mice, pika, hare, and elk; although in present distribution several of 

 these extend well into the southern region. Suggesting warmer 

 climatic conditions are bats and peccaries, in addition to crocodylid 

 and tapir. Among those forms whose most closely related living 

 representatives are now found much farther west are coyote, badger, 

 pika, a pumalike cat, and a pocket gopher tliat resembles Thomomys 

 more closely than it does Geoniys. 



The fauna as a whole is strongly indicative of a wooded region with 

 no lack of moisture. The floristic condition is suggested particularly 

 well by the spermophiles and jumping mice, and the plentiful supply 



