224 GYPSEOUS SERIES. [Ch. XVI. 



destroying, by its noxious properties, all the vegetation.* In like manner 

 the Pusanibio, or " Vinegar River," of Colombia, which rises at the foot 

 of Purace, an extinct volcano, 7,500 feet above the level of the sea, is 

 strongly impregnated with sulphuric and hydrochloric acids and with 

 oxide of iron. We may easily suppose the waters of such streams to 

 have properties noxious to marine animals, and in this manner the entire 

 absence of marine remains in the ossiferous gypsum may be explained.} 

 There are no pebbles or coarse sand in the gypsum ; a circumstance 

 which agrees well with the hypothesis that these beds were precipitated 

 from water holding sulphate of lime in solution, and floating the remains 

 of different animals. 



In this formation the relics of about fifty species of quadrupeds, in- 

 cluding the genera Paleotherium (see fig. 191), Anoplotherium (see fig. 

 190), and others, have been found, all extinct, and nearly four-fifths of 

 them belonging to a division of the order Pachydermata, which is now 

 represented by only four living species ; namely, three tapirs and the 

 daman of the Cape. "With them a few carnivorous animals are associated, 

 among which are the Hycenodon dasyuroides, and a species of dog, Canis 

 Parisiensis, and a weasel, Cynodon Parisiensis. Of the Podentia, are 

 found a squirrel ; of the Insectivora, a bat ; while the Marsupialia (an 

 order now confined to America, Australia, and some contiguous islands) 

 are represented by an opossum. 



Of birds, about ten species have been ascertained, the skeletons of some 

 of which are entire. None of them are referable to existing species.J 

 The same remark applies to the fish, according to MM. Cuvier and 

 Agassiz, as also to the reptiles. Among the last are crocodiles and tor- 

 toises of the genera Ends and Trionyx. 



The tribe of land quadrupeds most abundant in this formation is such 

 as now inhabits alluvial plains and marshes, and the banks of rivers and 

 lakes, a class most exposed to suffer by river inundations. Among these 

 were several species of Paleothere, a genus before alluded to (p. 210). 

 These were associated with the Anoplotherium, a tribe intermediate be- 

 tween pachyderms and ruminants. One of the three divisions of this 

 family was called by Cuvier Xiphodon (see fig. 235). Their forms were 

 slender and elegant, and one, named Xiphodon gracile (fig. 235), was 

 about the size of the chamois ; and Cuvier inferred from the skeleton that 

 it was as light, graceful, and agile as the gazelle. 



When the French osteologist declared, in the early part of the present 

 century, that all the fossil quadrupeds of the gypsum of Paris were ex- 

 tinct, the announcement of so startling a fact, on such high authority, 

 created a powerful sensation, and from that time a new impulse was 

 given throughout Europe to the progress of geological investigation. 

 Eminent naturalists, it is true, had long before maintained that the shells 



* Leyde Magaz. voor Wetensch Konst en Lett., partie v. cahier i. p. *71. Cited 

 by Rozet> Journ. de G6ologie, torn. i. p. 43. 



f M. C. Prevost, Submersions Iteratives, <fec. Kote 23. 

 X Cuvier, Oss. Foss., torn. iii. p. 255. 



