1888.] On the Structure, fyc, of Fossil Reptilia. 381 



Table IL 



Observer. 



Date. 



Value for r 

 in B.A. 

 units. 



"Value of 

 ohm in 

 centimetres 

 of mercury 

 at 0°. 



Lord Rayleigh and Mrs. Sidgwick .... 



1883 



0-95412 



1C6 -23 





1884 



•0-95374 



106 -33 





1885 



-95334 







1885 



0-95388 



105-93 





1887 



0-95349 



106 32 





1888 



0-95H31 



106 32 





1888 



0-95352 



106 -29 



The paper contains a discussion of the above results. It is shown 

 that probably Lord Rayleigh's value of r may be too high by as much 

 as 0*0002, in consequence of the fact that the mercury in his terminal 

 caps was 5° or 6° C, but no complete explanation of the differences 

 between his result and those of Rowland, Koblrausch, and ourselves, 

 has been found. The difficulty of working with tubes such as those 

 used by the Lorentz, 1 — 2 metres in length, and 1, 2, and 3 cm. in 

 diameter, may perhaps account for his value for the ohm, viz., 105 - 93. 



XL " Researches on the Structure, Organisation, and Classifica- 

 tion of the Fossil Reptilia. VI. On the Anomodont Reptilia 

 and their Allies." By H. G. Seeley, F.R.S. Received 

 June 20, 1888. 



(Abstract.) 



The author examines the structure of the skull in the Dicynodontia, 

 and discusses the interpretations of its elements and affinities given 

 by Sir Richard Owen, Professor Huxley, and Professor Cope, and 

 arrives at the conclusion that the interpretation of the bones of the 

 palate may be varied. The quadrate bone is found, though it is 

 absent from many specimens owing to loose articulation, and the 

 malleus is recognised as a normal element in the skull, which 

 articulates with the quadrate and is free, except at its extremities. 

 The palatine bones are internal to the pterygoids, and the ptery- 

 goids extend forward to the maxillary. The columella is found 

 in more than one specimen. Many new specimens are described 

 which further elucidate the structure of the skull. The first of 

 these shows that the upper part of the foramen magnum is formed 



2 f 2 



