498 



LAND MAMMALS IN THE WESTERN HEMISPHERE 



have been found, but, from the shape of the sacrum, it is evi- 

 dent that the tail was short. 



The Umbs were long, but more slender and less elongate 

 than in ^Macrauchenia, in which the growth of the neck did 

 not keep pace with that of the limbs, the 

 lengthening of the proboscis probably 

 compensating for this. The shoulder- 

 blade had two conspicuous metacromia, 

 very much as in the contemporary ftoxo- 

 dont, ^Nesodon, but shorter and more 

 widely separated.. The humerus was 

 short and quite slender and the fore-arm 

 bones, which were much longer, did not 

 coossify. The femur had a more slender 

 and rounded shaft than in ■\MacraiLchenia 

 and a much larger third trochanter; the 

 leg-bones were also separate from each 

 other. The tridactyl feet were so like 

 those of the Pampean genus, that no 

 particular account of them is necessary, 

 and the proportions of the limb segments 

 were similar in both genera, short upper 

 arm and lower leg, very long fore-arm 

 and thigh, and short feet. 



The appearance of the Uving animal, 

 as shown in the restoration, was no doubt 

 somewhat like that of ^[Macrauchenia, 

 M.,. magnum, u., un- but less bizarre. That there must have 

 ciform. V., rudimen- been some sort of & proboscis or pre- 



tary fifth metacarpal. , ., ,. • • t . i i j.v 



hensile upper up, is mdicated by the 

 greatly shortened nasal bones, but this may not have been 

 longer than in the existing Moose or Saiga Antelope. The 

 long neck, short body and tail and long limbs suggest an 

 animal not unlike a Guanaco, but larger and heavier. The 

 hair may or may not have had the woolly character given 



M 



Fig. 247. Left manus of 

 iTheosodon. S., scaph- 

 oid. L., lunar. Py., 

 pyramidal. Tm., trape- 

 zium. Td., trapezoid. 



