Manchester Memoirs, Vol. Iv. (191 1), ^0. 18. 3 



The surface of the palatines is generally flat, but 

 there is a slight median ridge separating two shallow 

 grooves. 



The sub-orbital vacuities are short and broad and 

 the ecto-pterygoids very feeble. 



Steneosanriis stephani comes from the Cornbrash and 

 is hence one of the earlier types of the genus. It is ot 

 interest to compare it with other early species. 



In his "Notes paleontologiques" Eudes-Delongchamps 

 figures a plaster cast of a skull from the English Corn- 

 brash which he identifies with his 5. Boutilieri. This 

 skull consists almost entirely of rostrum and is hence 

 rather difficult to compare with S. stephani: so far as 

 corresponding portions of the two skulls occur, they agree, 

 and it is probable that they belong to the same species. 

 The Bristol Museum contains another copy of this cast, 

 and I found there a cast of the back of a Steneosaur skull 

 which may belong to it ; it agrees closely with S. stephani, 

 but as there is no real evidence that it belongs to the 

 snout, I think it is preferable to keep the name stephani 

 for the Closworth skull. 



Compared with typical late members of the genus 

 Steneosani-us stephani approximates to the Mystriosanrns 

 type in its unusually large pterygoids and its relatively 

 small supra-temporal fossae : from this genus, however, 

 which I have studied in a magnificent series of specimens 

 of the species Brongniarti at Manchester, >S". stephani 

 differs in the absence of pre-orbital vacuities, in not having 

 the posterior narial opening pointed in front, and in the 

 much smaller pterygoids. 



In fact, in the condition of its pterygoids and supra- 

 temporal fossae, it is exactly intermediate between 

 Mystriosanrns and such a species as Steneosanrns Jiebcrti. 



