154 On the probable //af*//* o/'Struthiomiinus. 



the claws of the opposed fingers couUl close without the ba3;il 

 parts of the fiiis^ers beiii<^ brought togetlier. 



This structure of the inanus is altogether different from tho 

 structure of the niauus in the sloths, with which it has been 

 compared, for these have no thumb; therefore its function 

 was evidently different. Besides this, it differs also from the 

 hand of climbing, branch-catching animal-*, for in these latter 

 it is of importance that in ordei" to augment the friction, the 

 whole interior surface of tlie hand should l)e apj)lied to the 

 object it is grasping, and the base of the fingers more so than 

 the points. iSurely the fingers of Struthiomimus were adapted 

 for liolding something, but not for pressing. The hand of 

 this animal seems admirably adapted for lifting objects from 

 the ground that would be spoilt by pressing and that had no 

 projections whereby they might be lifted, but were evenly 

 rounded and sniooth all over. By opening the l>ng fingers, 

 by pushing then the sharp claws of tho second and third 

 digit between su<;h objects and the surface they were laying 

 on atid holding them with the thumbs, such objects might be 

 surely and easily removed, even when of considerable weight 

 or size. 



By the hypothesis that Strulhiomimus used while standing 

 to li(t objects from the ground, we get quite a satisfactory 

 explanation for the great length of its arms, for these had to 

 be in correlation with the strongly elongated hind legs tliat 

 served for running. 



(3) The edentulous maxillaries of Struthiomimus show 

 that the maxilhuy was not used for the trituration or the 

 crushing of tlie tood, for if it crushed its food it is difficult to 

 understand why its teeth should have been reduced. This 

 militates against its having eaten crabs, crayfish, sea-urchins, 

 or similar material. The sharp and pointed beak indicates 

 t!iat the food was of such nature that not comparatively 

 blunt premaxillaries but a pincers-like object had to be brought 

 into action, and the strong muscles of the lower jaw prove 

 beyond doubt that the object that had to be cut out with 

 the sharp end of the beak was resistant, and although not 

 hard, yet tough, and perhaps even leathery. This powerful 

 musculature is a strong argument against the hypothesis of 

 Struthiomimus having taken the same sort of food as the 

 living ostrich or of having lived on soft fruit, leaves, or 

 insects. Probably it was not leathery material cut by the 

 beak that served for food, for, firstly, the nutritive value of 

 all such material is generally small, and, secondly, the 

 maxillaries would again have been brought into action with 

 something soft beneath. To assume tiiat the soft part of the 



