chap. xi. Banda Oriental. 339 



that just described in the more eastern parts of the 

 province. Although from the smooth and unbroken 

 state of the country, I never obtained a section of this 

 latter deposit close to the foot of the higher tertiary 

 hills, yet I have not the least doubt that it is of quite 

 subsequent origin ; having been deposited after the sea 

 had worn the tertiary strata into the cliff-bounded hills. 

 This later formation, which is certainly the equivalent 

 of that of the Pampas, is well seen in the valleys in the 

 estancia of Berquelo, near Mercedes ; it here consists of 

 reddish earth, full of rounded grains of quartz, and 

 with some small concretions of tosca-rock arranged in 

 horizontal lines, so as perfectly to resemble, except in 

 containing a little calcareous matter, the formation in 

 the eastern parts of Banda Oriental, in Entre Bios, and 

 at other places : in this .estancia the skeleton of a great 

 Edental quadruped was found. In the valley of the 

 Sarandis, at the distance of only a few miles, this de- 

 posit has a somewhat different character, being whiter, 

 softer, finer-grained, and full of little cavities, and con- 

 sequently of little specific gravity ; nor does it contain 

 any concretions or calcareous matter : I here procured 

 a head, which when first discovered must have been 

 quite perfect, of the Toxodon Platensis, another of a 

 Mylodon, 1 perhaps M. Barwinii^ and a large piece of 

 dermal armour, differing from that of the Glyptodon 

 clavipes. These bones are remarkable from their ex- 

 traordinarily fresh appearance ; when held over a lamp 

 of spirits of wine, they give out a strong odour and 

 burn with a small flame ; Mr. T. Beeks has been so kind 

 as to analyse some of the fragments, and he finds that 



1 This head was at first considered by Professor Owen (in the 

 ' Zoology of the Beagle's Voyage ') as belonging to a distinct genus, 

 namely, Glossotherium. 



