206 Dr. A. S. Woodicard — L. Pliocene Bone-heel of Concud. 



of Eipparion, which may perhaps belong to a second species. We 

 found one mandible and one upper jaw of Bhinoceros, with teeth 

 closely resembling those of B. Schleiermacheri, but not quite identical. 

 Some decayed fragments of limb-bones and a small piece of a tooth, 

 not worth preservation, clearly represented Mastodon. A mandibular 

 ramus, various teeth, and horn-cores are identifiable with Gazella 

 hrevicornis. Other teeth represent an undetermined larger antelope. 

 Vilanova has also recorded doubtful traces of Cervus and Hycena 

 eximia,^ while Cortazar mentions the discovery of teeth of Sus.^ 



A deposit which yields remains of so interesting a mammalian 

 fauna to the casual work of a few days with a small party of men, 

 deserves further systematic exploration. It is true that in all the 

 spots we examined near Concud excavations are rendered difficult 

 by the mass of overlying limestones, which, in the absence of 

 timber, need to be supported by pillars of masonry when the marl 

 and bone-bed are removed. Similar bones, however, have been 

 noticed in many other parts of the Teruel basin, and it is quite 

 likely that extended search would lead to the discovery of better 

 preserved and more readily accessible material. 



Such renewed and extended exploration would also be of much 

 interest from a purely geological point of view, considering the 

 result of recent researches in some of the so-called Tertiary lake 

 basins of western North America, and in the remarkable Tarija 

 Valley in Bolivia. According to Matthew " and Hatcher,* the 

 North American deposits in question, with their wonderful bone-beds, 

 cannot have been formed in great sheets of water, but are partly 

 wind-borne, partly fluviatile, partly formed in temporary pools. 

 According to Nordenskjold,'^ the Tarija Valley was once a steppe, 

 and the remains of Mastodon and other quadrupeds now found 

 buried there represent animals which lived on the spot and were 

 engulphed in shifting pools and mud-flats. Hatcher, indeed, con- 

 siders that similar deposits are now accumulating on some of the 

 flood-plains in the higher reaches of the great rivers of South 

 America. Quoting a recent observer, Mr. H. H. Smith, he alludes 

 to a plain about 400 miles long and in some places 150 miles wide, 

 which is periodically flooded by the Eiver Paraguay. " Even at 

 low water at least one-fourth of it is flooded : when the river is 

 at its highest the whole plain is a vast lake covered with floating 

 grass and weeds ; it is possible to pass almost straight across it 

 in a canoe, though with great difficulty. Only a few islands 

 remain here and there ; jaguars, deer, and other animals take 

 refuge on them." 



1 Named Hi/cenictis ffr<sca? by Vilanova, redetermined by Gaudry, " Les Ancetres 

 de nos Animaux," 1888, p. 202. 



2 D. de Cortiizar: loc. cit., p. 449. 



3 "W. D. Matthew, "Is the White Eiver Tertiary an Eolian Formation?" : 

 Amer. Nat., vol. xxxiii (1899), pp. 403-408. 



* J. B. Hatcher, " Origin of the Oligocene and Miocene Deposits of the Great 

 Plains" : Proc. Amer. Phil. Soc, vol. xli (1902), pp. 113-131. 



5 E. Nordenskjold, " Ueber die Saugethier-fossilien im Tarijathal, Sildamerika " : 

 Bull. Geol. Inst. Upsala, vol. v (1901), pp. 261-266. 



