c,-^ 



TIIK ANxNALS 



AND 



MAGAZINE OF NATURAL HISTORY. 



[EIGHTH SERIES.] 

 No. 45. SEPTEMBER 1911. 



XL. — The Skull of Diadcmodon, with Xoles on those of 

 some other Cynodonts. By D. M. S. Watson, M.Sc, the 

 Victoria University of Mancliester. 



Our knowledge of t]u> skull of Cynodonts dates from 1860, 

 wlien Owen described the type specimen of Galesaurus 

 planiceps ; hut our more detailed information depends almost 

 entirely on the description by the late Prof. H. G. Seeley of 

 the wonderfully perfect skulls of Go)nj)liognathiis and Cyno- 

 gnathus, which were developed by Mr. R. Hall of the British 

 Museum under his supervision. More recently Dr. R. 

 Broom has added something to our knowledge by amending 

 some of Seeley's descriptions and by the description of some 

 new specimens. Quite recently W. K. Gregory, in his 

 excellent work 'The Orders of Manmials/ has published a 

 figure of the under surface of a Cynoynathus skull drawn from 

 a plaster east, with the assistance of figures j)ul)lislied by 

 Seeley and Broom ; he has added to this a clear discussion 

 of its structure, and his description may be regarded as a 

 summary of what is actually known. 



Amongst the specimens obtained by Seeley in South 

 Africa, which are now in the British jMuscum, is a small 

 skull (R. 35S7) from Winnaarsbaken in Cape Colony be- 

 longing to tlie genus Diademodon. This skull, which is 

 almost completely undistorted, is preserved in a matrix of 

 liver-coloured micaceous shale, passing occasionally into a 



Ann. ct' Mag. N. Hist. !Ser. 8. Vol. viii. 20 



