Mr. C. Forster-Cooper on Thaumastotherium osborni. 381 



As some of the bones are not yet fully developed, a further 

 description cannot be attempted here. In fact, there is .some 

 difficulty in finding material for the purposes of comparison, 

 owing to the aberrant character of the bones. The astragalus, 

 as may be seen from the figure, is Perissodactyle rather than 

 anything else — at all events, it is not Proboscidian ; more- 

 over, it (as well as the other foot-bones, of which there are a 

 considerable number) is more comparable with those o£ the 

 Rhinoceros than anything else, in spite of great differences 

 in proportion and size. The two podial bones point to an 

 animal exceedingly dolichopodous, a remarkable feature when 

 the heavy build of the body is taken into consideration. 



The femur and humerus are rather Proboscidian at first 

 sight, and are probably thus modified in each case as adapta- 

 tions to weight-carrying. The absence of a third trochanter 

 does not necessarily imply that the owner is not a Perisso- 

 dactyle, seeing that the Titanotheres were without one. 



It is the vertebise, however, which show this animal in the 

 strangest light, for, in addition to the unique structure of the 

 vertebrarterial canal described above, the shape and measure- 

 ments of the bones themselves point to a very long neck. 

 At the end of this long neck there must have been a very 

 large skull, witness the size of the condylar facets in the 

 atlas. It is very unfortunate that no trace of this skull 

 could be found to give us an idea of its shape ; but if we 

 take the length of the skull as about four times the width of 

 the condyles (a proportion found in some of the rhinoceroses), 

 we get a head measuring well over a yard in length. The 

 weight of a mass like this at the end of a four-foot neck (a 

 moderate estimate) would require and account for some 

 strange modifications of the cervical vertebra?. 



It is thus impossible at present to give an idea of the 

 position of this animal. I believe all the bones described to 

 belong to one animal both from their close association in the 

 bone-bed and from the universal absence in these deposit? of 

 a trace of any other form to which they could belong. The 

 Elephants and Rhinoceroses living at the same time, of 

 which considerable remains have been found, point to forms 

 of small or not more than medium size (Paraceratherium 

 bugtiense, the next largest animal obtained, is about as large 

 as a modern rhinoceros). 



It is to be hoped, however, that a stricter examination and 

 comparison of all the available material will throw some more 

 light on the structure and relationships of this interesting 

 form. 



