28 



Now the species which I originally described imder the name of 

 Cimoliornis diomedeus comes precisely under this category : it has 

 formed the groundwork of later generalizations, which have led to its 

 being embraced by another genus. In this case the Committee of 

 Nomenclature, whilst determining that the specific name should be 

 retained, recommend that the describer should " append to the ori- 

 ginal authority for the species, when not applying to the genus also, 

 some distinctive mark, such as {sp.), implying an exclusive reference 

 to the specific name." In conformity with the above recommenda- 

 tion, the gigantic species of Pterodactyle, of which parts have been 

 described by Mr. Bowerbank, and parts previously by myself, would 

 be entered into the Zoological Catalogues as follows : — 



Pterodactylus diomedeus, Owen (sp.). Proceedings of the Zoolo- 

 gical Society, January 1851. 



Cimoliornis diomedrens, Ibid., British Fossil Mammals and Birds, 

 p. 545, cuts 230, 231 (1843-1846). 



Osteornis diomedoeus, Gervais, These sur les Oiseaux FossOes, 8vo, 

 p. 38 (1844). 



Pterodactylus giganteus, Bowerbank, Quarterly Journal of the 

 Geological Society, vol. iv. p. 10. pi. 2. figs. 1 & 4 (1848). 



Leaving, however, the question of names, regarding which I have 

 no personal feeling except that they should indicate their objects 

 without ambiguity or obvious impropriety, I proceed to lay before 

 the same Society to which Mr. Bowerbank has communicated his last 

 interesting and important discovery, similar evidence of a third spe- 

 cies of Pterodactyle from the chalk, intermediate in size between the 

 species of which the jaws were figured as the Pterodactylus giganteus 

 in 1845, and the truly gigantic species which he has named Ptero- 

 dactylus Cuvieri. 



The specimens, which consist of two portions of the upper jaw, 

 form part of that gentleman's collection, and were in fact exhibited 

 on the table, but unnoticed, at our last meeting, their true nature not 

 having been recognised. The chief portion might well indeed be mis- 

 taken, at first sight, for a crushed portion of an ordinary long bone ; 

 and it was not until after a close comparison of several specimens of 

 these rare and interesting remains of Pterodactyles, kindly confided 

 to me by Mrs. Smith of Tonbridge Wells, Mr. Toulmin Smith of 

 Highgate, Mr. Charles of ISIaidstone, and by Mr. Bowerbank him- 

 self, for description in my forthcoming ' Monograph on the Fossil 

 Reptiles of the Chalk,' that I discovered them to be parts of a skull 

 of an imdescribed species of Pterodactyle. 



In order to make this understood, it will be necessary to premise a 

 few words on the Pterodactyles in general, and on some of the cha- 

 racters of the jaw of the Pterodactylus Cuvieri in particular. 



The Order Pterosauria includes species of flying reptiles so modi- 

 fied in regard to the structure and proportions of the skull, the dis- 

 position of the teeth, and the development of the tail, as to be refer- 

 able even according to the partial knowledge we now possess of this 

 once extensive group, to different genera. 



