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PATAGONIAN EXPEDITIONS : PALAEONTOLOGY. 
the usual kind. The other tarsal bones resemble those of the Santa Cruz 
genus in character and arrangement, except that they are relatively shorter 
proximo-distally and much broader and more massive, a change which is 
particularly evident in the shape of the ectocuneiform, and in the overlap- 
ping of the latter by the cuboid. The metatarsals also are proportion- 
Toxodon burmeisteri : A, left pes, dorsum, Nesodon imbricatus : Left pes, dorsum, X J. 
X | B, the same, external view. La Plata 
Museum. 
ately shorter and much heavier and are of more nearly equal size, though 
mt. Ill is somewhat longer, broader and more compressed planto-dorsally 
than II and IV. The phalanges are shorter, broader and heavier than 
those of Nesodon and the unguals have more the appearance of those of 
the rhinoceroses. 
Restoration. (PI. XII, fig. 2.) The Santa Cruz fauna is largely made 
up of mammals which, from our modern standpoint, have a very curious 
and bizarre appearance. Among the more striking of these is Nesodon , 
which bears but a distant resemblance to any known ungulate of the 
northern hemisphere, recent or extinct. The short, deep and massive 
head has a decided suggestion of likeness to the rodent skull, though this 
likeness is not so strong as in the Typotheria. The neck is short and 
heavy and most of its vertebrae have neural spines of unusual height. 
