THE AM ERIC AX MUSEUM JOURNAL 



the heavy block ot solid sandstone in 

 which it had lain embedded through 

 the ages. 



At the time of death the animal was 

 entombed in the position shown, with 

 the neck bent sharply backward so that 

 the back of the skull rested upon the 

 top of the hip girdle; as the rock was 

 gradually removed from the bones in 

 the Museum laboratory the animal was 

 found to be in exactly the posture 

 shown in the accompanying photo- 

 graph except the limbs, which we found 

 it necessary to alter slightly in order to 

 expose the two sides. In the restora- 

 tion the arms were outstretched in front 

 and the legs placed in a similar bent 

 posture as if in motion. 



The discovery of this skull and fore 

 limb occasioned one of the greatest 

 surprises in the whole history of the 

 science of vertebrate palaeontology. It 

 had confidently been predicted that 

 these "bird mimics" were flesh eaters, 

 and the present writer, at least, ex- 

 pected to find the skull provided 

 with sharply pointed, recurved teeth, 

 adapted to seizing and holding a 



To illustrate the tree-climbing fore limb of the three-toed sloth, Bradypus, 

 ■which iu some respects resembles the fore limb of the "ostrich" dinosaur, 

 Strut hioniimus. After De Blainville 



swiftly moving and struggling prey. 

 Consistent with this theory, it was an- 

 ticipated that the fore limb and the 

 hand would be specialized as grasping 

 organs adapted to snatching and hold- 

 ing a struggling bird or small reptile, 

 as in the theory of the ancestral "bird 

 robber" dinosaur. On the contrary, 

 the "ostrich mimic" dinosaur proves 

 both in its head and in its limb struc- 

 ture to be not raptorial at all but 

 probably a comparatively harmless, in- 

 offensive creature. 



The extremely small head and slen- 

 der jaws, which are entirely toothless, 

 most nearly resemble those of the living 

 ostrich. Unlike any dinosaur yet dis- 

 covered there is a total absence of teeth 

 and the indications are that the jaws 

 had been converted into narrow horny 

 beaks somewhat similar to those of the 

 ostriches of today. The head as a whole 

 is one third longer than in the present- 

 day ostriches, although the tail and 

 backbone combined are more than thir- 

 teen feet in length. The jaws are rela- 

 tively deeper and more powerful than 

 those of the ostrich, but all the areas of 

 muscular attach- 

 ment are much 

 slighter than in 

 any of the car- 

 nivorous dino- 

 saurs, indicating 

 that this animal 

 had long since lost 

 all the flesh-eating 

 adaptations of the 

 skull, and had be- 

 come fitted for the 

 consumption of 

 some variety of 

 relatively soft and 

 tender food. The 

 neck is long and 

 extremely flexible, 

 reminding one of 



