Tvof. S. G. Seeley — On the Genus Ornithocheirns. 19 



from the sides of the specimen. This species nearly resembles the 

 Oniithoclieirus SedgioicJci of Owen, but diifers in the less depth of 

 the jaw, the greater height of the inter-alveolar palatal ridge, the 

 niuch narrower palatal groove, and the greater distance between the 

 tooth-sockets. It resembles that species in having the tooth-sockets 

 in pairs opposite to each other, in the ovate form of the sockets, and 

 in the compressed aspect of the jaw, though the inferior keel in this 

 species is much more roixnded. In the Pterodactyliis Cuvieri, tlie 

 lower jaw of which has not been figured, except in an anterior 

 fragment (plate xii. fig. 5, Ornithosauria), the jaw entirely wants the 

 slender dagger-like shape. 



One of the most distinctive bones of the skeleton of OrmtliocJieirus 

 is the scapula. In many other Ornithosaurs, such as Dimorpliodon, 

 the bone has a very avian aspect, but in this genus its form, 

 though thoroughly distinctive, perhaps rather suggests the Crocodile, 

 and as Mr. Keed's collection contains one of the most perfect 

 specimens of this bone which I have seen from the Cambridge 

 Greensand (Plate I. Figs, la, Ih), I by his kindness append a short 

 note upon its characters. 



The extreme length of the specimen from proximal to distal end 

 is about nine centimetres. It is best pi'eserved on the internal side, 

 which is concave in length. The proximal end is expanded, and 

 shows a small portion of the ai'ticular surface, but the bone 

 there is a good deal decomjDosed, and all traice of its union 

 with the coracoid, probably sutural, is obliterated. The bone 

 also expands a little at the distal end, and the middle of the 

 shaft, which is compressed and constricted, somewhat thickens 

 distally. The bone terminates distally in a broad ovate flattened 

 surface, which is smooth and moderately convex in length. The out- 

 line is rounded on the coracoid side, and compressed on the posterior 

 margin. The extreme width of this end is about two and a half 

 centimetres, and where thickest is about one and a half centimetre 

 through. This surface is at right angles with the concave side of 

 the shaft. In its most constricted middle portion the width of the 

 shaft is about fifteen millimetres, and its thickness from the com- 

 paratively flattened under side to the more convex outer side is about 

 twelve millimetres. The proximal end of the bone terminates in a 

 large rhomboid mass, which is somewhat cup-shaped on the inner 

 side. Its extreme width is about four centimetres. It is broken on 

 both sides of the median articular surface, which is a little concave 

 in length, and measures one and a half centimetre. Its transverse 

 measurement is about seven millimetres, and in this direction is 

 convex. The fracture on the outer side is probably small, since more 

 perfect specimens show the bone here to terminate in a rounded and 

 compressed tuberosity not greatly different in outline from that 

 indicated by the fossil. The long fracture on the side towards the 

 coracoid, which measures about two centimetres in length, may have 

 removed a small portion of the bone. The lateral outline of the 

 shaft posterior to this fracture on the coracoid side is deeply concave 

 proximally and nearly straight towards the distal end. The corre- 



