ANATOMY OF THE ANTHROPOID APES. 197 



paper has been recorded by Wilder. The extensor indicis, which I found to supply 

 the index only, may in the Common Chimpanzee send a tendon to the middle finger 

 also. I have referred above to Mr. Sutton's statement that the fibular head of the 

 soleus is the only head present, but that it is more extensive than in the present species. 

 Sir G. Humphry found in a Common Chimpanzee the fibular origin restricted, as in 

 the case of " Sally," to the head of the fibula ; but in the specimen dissected by him the 

 tibial head also was present. Dr. Chapman i found no plantaris in the Chimpanzee ^ 

 dissected by him, and no transversus pedis. It is clear from the above very brief and 

 incomplete notes upon recorded investigations into the myology of the Common 

 Chimpanzee that it is not easy at present to say exactly what is the normal arrangement 

 of the muscular structure of that animal ; we are evidently not yet in a position to 

 discriminate between what are variations and what are characteristic arrangements. 

 If this is the case with the Common Chimpanzee, which has been dissected by so many 

 anatomists, it is obviously much more the case with the Bald-headed Chimpanzee, of 

 which, at present, only a single specimen has been dissected. I do not think it, there- 

 fore, worth while to attempt an exhaustive comparison of its muscles with those of 

 other Anthropoids ; the value of such a comparison would be very far indeed from 

 being commensurate with the labour of collecting various papers and abstracting the 

 necessary data. There is no reason to suppose that when other examples of Troglodytes 

 calvus have been dissected they will prove to be identical in every point with the 

 individual studied by myself. I must therefore leave to further workers the task of 

 constructing a muscle formula of this Ape for comparison with other Anthropoids. 



§ 9. The Palate. 

 The accompanying drawing (Plate XXV. fig. 2) illustrates the palatal rugee of this 

 Chimpanzee. It will be observed that the folds upon the hard palate, although fairly 

 well marked, are iiuegular in their arrangement and incomplete compared with what 

 they are in the lower Apes. This holds good for all the Anthropoid Apes so far as 

 they are known, and for Man. Sir Eichard Owen says ^, on the other hand, " In the 

 higher Quadrumana the palate is smooth or unridged as in Man." The palate is 

 certainly smoother in Man than in the Chimpanzee, but there are ridges which, how- 

 ever, are much fewer than in the Ape. 



The drawing (Plate XXV. fig. 2) precludes the necessity of an elaborate description 



f the palatal ridges of Troglodytes calvus, which, moreover, possibly have some j-ange 



of variation as they have in Man ^ ; it is, however (in my opinion), important to illus- 



' " On the Structure of the Chimpanzee," Proc. Acad. Nat. Sci. Philadelphia, 1879, p. 52. 

 ^ Its absence is also asserted by Bisohoff and Briihl. Hartmann, however (' Der GoriUa,' p. 52), says that 

 it is normally present. 



^ Comp. Anat. vol. iii. p. 396. 



* H. AUen, " The Palatal Rugae in Man," Proc. Acad. Nat. Sci. Philad. 1888, p. 254. 



