THE MOUNTED SKELETON OE BRONTOSAURUS n 



surface of cartilage. The pressure was thus much better dis- 

 tributed over the joint, and the full weight of the part of the 

 animal above water (reduced as it was by the cellular construc- 

 tion of the bones) might be borne on these joints without the 

 cartilage giving away. 



Looking at the mounted skeleton we may see that if a line be 

 drawn from the hip-joint to the shoulder-blade, all the bones 

 below this are massive, all above (including neck and head) are 

 lightly constructed. This line then may be taken to indicate 

 the average water-line, so to speak, of this Leviathan of the 

 Shallows. The long neck, however, would enable the animal to 

 wade to a considerable depth, and it might forage for food either 

 in the branches or the tops of trees or, more probably, among 

 the soft succulent water-plants of the bottom. The row of short, 

 spoon-shaped, stubby teeth around the front of the mouth would 

 serve to bite or pull off soft leaves and water-plants, but the 

 animal evidently could not masticate its food, and must have 

 swallowed it without chewing, as do modern reptiles and birds. 



The brain-case occupies only a small part of the back of the 

 skull, so that the brain must have been small even for a reptile, 

 and its organization (as inferred from the form of the brain-cast) 

 indicates a very low grade of intelligence. Much larger than the 

 brain proper was the spinal cord, especially in the region of the 

 sacrum, controlling most of the reflex and involuntary actions 

 of the huge organism. Hence we can best regard the Bronto- 

 saurus as a great, slow-moving animal-automaton, a vast store- 

 house of organized matter directed chiefly or solely by instinct 

 and to a very limited degree, if at all, by conscious intelligence. 

 Its huge size and its imperfect organization, as compared with 

 the great quadrupeds of to-day, rendered its movements slow and 

 clumsy; its small and low brain shows that it must have been 

 automatic, instinctive and unintelligent. 



COMPOSITION OF THIS SKELETON. 



The principal specimen, No. 460, is from the Nine Mile Crossing of the 

 Little Medicine Bow River, Wyoming. It consists of the 5th, 6th and 8th to 

 13th cervical vertebrsc, ist to 9th dorsal and 3d to igth caudal vertebra?, all the 

 ribs, both coracoids, parts of sacrum and ilia, both ischia and pubes, left femur 



