the Skeleton of Diplodocus Camegiei. 367 



Century Magazine, September, 1904. In the former one can see 

 clearly that Professor Osborn has disregarded the true proportions of 



Diplodocus, making the neck far too long, the fore-limbs too small, 



and giving it a very weak chest ! 



The Carpal and Tarsal Bones. 



If Diplodocus walked as a mamma], then we can only say that its 

 walking must have been of a very inefficient character. Have the 

 American naturalists ever considered this point — that Diplodocus 

 seems to possess very few wrist and ankle bones? They were 

 evidently largely encased in cartilage, as in living reptiles and in 

 all the early amphibians and reptiles. This, we maintain, renders it 

 quite impossible for the animal in question to have walked like an 

 elephant. More bones would be required in the joints to give the 

 necessary strength to bear so great a weight, and also to render them 

 sufficiently flexible their surfaces would not have been so flat. On 

 comparing the carpals and tarsals with those of living reptiles, the 

 writer finds that they approach more nearly to those of the Brazilian 

 tortoise than to anything else. In the hind-limb there is the same 

 fusion of several bones into one, thus forming a single bone which 

 probably consisted of the fibiale, intermedium, centrale, and tibiale ; 

 in the carpus, we seem to have the radiale and centrale combined 

 and perhaps the intermedium. Now, if these bones so much resemble 

 the corresponding bones of a tortoise, is it not allowable and reason- 

 able to argue that the limbs were used in the same manner, and 

 especially that the joints were not subjected to such extensive or so 

 frequent flexure as in the case of an elephant? Consider how 

 widely the mode of progression of a tortoise differs from that of 

 a mammal. The former slowly drags the limb round much as an 

 oarsman might slowly bring his oar forward for the next stroke, while 

 the elephant quickly brings it forward much as a man brings his leg 

 up for the next stride, and in so doing he bends the tarsal bones in 

 a way that is not possible to any reptile. 



But, after all, the writer would urge that perhaps the best evidence 

 for the view here maintained is to be found in the nature of the 

 pelvic girdle. It is beyond all doubt crocodilian, and well adapted 

 to hold the kind of muscles required to work the hind-leg sideways 

 like the oar of a boat. It certainly does not possess that arching- 

 over shape necessary in the case of an animal that uses its hind-leg 

 for movements up and down like a pendulum (see p. 362, Fig. 3). 

 There simply is no room for the big muscles that would be required 

 for that kind of movement. 



The Fore-limbs. (Figs. 5-7.) 



The writer has long maintained that the worst of all mistakes made 

 in the setting up of the skeleton now under consideration is the way 

 in which the fore-limbs are set up. It is hardly too much to say that, 

 in the whole animal kingdom, there is not to be found any limb 

 arranged in such a weird manner as this ! Taking a side view of the 

 skeleton, one sees with positive amazement that the bones make an 



