) 
394 PROCEEDINGS OF THE GEOLOGICAL socrery. —[ Mar. 29, 
Marcu 23, 1870. 
Frederick Antony Potter, Esq., B.Sc., Assoc. Royal School of Mines; 
Cromford Derbyshire, was elected a Fellow of the Society. 
The following communications were read :— 
1. Notice of a Fragment of a Repritran Sxutx from the UrrEr 
_ Creraczous of Grinpacu. By Dr. Emanvet Bunzet. 
[Communicated by Prof. Huxley, F.R.S. &c.] 
(Abstract.) 
Tue bone described by the author was found by Prof. Suess in a 
coal-mine belonging to the Gosau formation at Grimbach, near Wiener 
Neustadt, from which Prof. Suess obtained numerous other bones 
also belonging to terrestrial reptiles. 
The author stated that the reptilian character of the bone ap- 
peared at the first glance, as it shows a single condyle and a tem 
poral fossa resembling that of a Crocodile; but it has some pecu- 
liarities, such as the convexity of the occiput and its gentle passage 
into the roof of the skull, without forming an angle as in other 
reptiles, the transverse ridge in the occipital region, the want of 
sutures between the bones, the globular form of the condyle, the 
horizontality of the base, the ascending direction of the clivus, and 
the large brain-cavity, which render it impossible to refer the animal _ 
to which this bone belonged to any recognized order of Reptiles. 
The known skulls of Dinosaurians have a steep occiput, and ex- 
hibit more of the Lacertilian type; the fragment described by the 
author rather resembled that of a bird. The author consequently 
suggested the formation of a new order of fossil Reptiles, Ornitho- 
cephala, nearly allied to the Ornithoscelida of Prof. Huxley. 
For the animal of which this fragment is the only known relic, 
the author proposed the generic name of Struthiosaurus. 
2. On the Patmonronoey of the Junction Beps of the LowEr and 
Mrppie Lis in Groucnstersuire. By Raten Tare, Esq., Assoc. 
Lin. Soc., F.G:S., &c. 
[Prats XXVI.] 
Previous to the writings of Messrs. Oppel and Wright on the classi- 
fication of the various members of the Lias, that portion of the 
system which intervenes between the great limestone series of the 
Lower Lias below and the Marlstone above was referred to the 
Lower Lias; but these authors have drawn the line of demarcation 
between the Lower and Middle Tias through the mass of clays and 
shales which constitute the median portion of that system, the zone 
of Ammonites raricostatus being the uppermost member of the 
Lower Lias, and that of Ammonites Jamesoni the lowermost member 
of the Middle Lias. Now it has not been shown in any English 
publication that this separation harmonizes with the distribution of 
organic remains, and by the superficial reader the boundary-line may 
well be considered an arbitrary one; it will be my endeavour to 
a the division of the Lower and Middle Lias as drawn by 
ppel. 
