THE ANXALS 



AND 



MAGAZINE OF x\ATURAL HISTORY 



[EIGHTH SERIES.] 

 No. 45. SEPTEMBER 1911. 



XL. — T/ie Skull of Diademodon, with Notes on those of 

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

 A'ictoria University of Manchester. 



Our knowledge of tho skull of Cynodonts dates from 18G0, 

 when Owen described the type specimen of Galesaurus 

 planiceps ; but our more detailed informntiou depends almost 

 entirely on the deserij)tiou by the late Prof. H. U. Seeley of 

 the wonderfully perfect skulls of GompJiognatlius and Cyno- 

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

 Museum under his supervision. i\Iore 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 ]\Iammals/ has published a 

 figure of the under surface of a Cynognathus skull drawn from 

 a plaster east, with the assistance of figures published 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, whicl» are now in the British Museum, is a small 

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

 longing to the genus Diademodon. This skull, which is 

 almost completely undistorted, is preserved in a matrix of 

 liver-coloured micaceous shale, passing occasionally into a 



Ann. d- Mag. N. Hist. !Ser. 8. Vol. viii. 20 



