-^ OSBORN. 



The age of these various deposits is a very important matter 

 For reasons given above and below certain of these deposits ap- 

 pear to have overlapped or extended through one or more periods 

 of regular stratigraphic deposition as follows : 



Egerkingen (Canton Vaud) Middle to Upper Eocene 



inclusive. 

 Lissieu, Middle to Upper Eocene inclusive. 

 Fronstetten (Swabian Alps), Mainly Upper Eocene. 

 Heidenheim (Mittelfranken), 

 Mauremont (Canton Vaud) 



Oerlinger Thai. u. Eselsberg, Ulm, Upper Eocene. 

 Quercy, Caylux, Mouillac, Phosphorites, Upper Eocene 

 to Middle OHgocene. 

 The Phosphorites du Quercy, the most extensive and 

 famous fissure deposits of this kind, occur in Jurassic calcareous 

 fissures of 3 to 6 metres in width and 35 metres in length The 

 matnx is a phosphate of lime probably of mineral spring origin 

 (FiLHOL, 77, p. 1-2;). The fauna enjoyed a warm and moist 

 climate. Filhol believes that death was caused by asphyxia- 

 tion due to poisonous vapors arising from hot springs, many 

 skeletons being found complete and showing no marks of teeth 

 In contrast with Quercy, which contains a fauna of extraordi- 

 nary richness, beauty and completeness, Egerkingen and Lis- 

 SIEU have yielded merely isolated teeth. 



The Quercy fauna according to Filhol predominates in 

 Upper Eocene or Gypsc types. The Phosphorite rhinoceroses 

 have by some authors and in many museums been referred to 

 A. lemanensc and A. minntum, both of which are Upper Oligo- 

 cene or Aquitanean species—//./^ ts an error; the two rhinocer- 

 oses which this formation contains are probably the Ron-o- 

 thcrmm vclaumim Axu.^^y,, found also in Ronzon, and another 

 species much simpler than the Aquitanean Diccrathcrium minu- 

 turn Cuv. {R. plairoceros Duvernoy), of Moissac. This small 

 species has simple upper premolars ; it either belono-s to A 

 gaudryi Rames, or represents a distinct species. These facts 

 with the tables published by Filhol ('77) show that the Quercy 

 deposition probably terminated in the lower or Middle Olio-ocene 



