H. G. SEELET ON EHAMPHOCEPHALUS PKESTWICHI. 29 



limetres. The bone widens in front a little, but the front of the orbit 

 is formed, as usual, by the prefrontal bone (p/). The median suture 

 between the frontals is clear. There is a deep concavity between 

 the orbits in front, which is formed by the margins of the frontal 

 bone being elevated so as to form an upper orbital border, which 

 recalls the condition in Crocodiles. There are also elevated ridges 

 behind the orbits. The little that is seen of the inner orbital 

 border is smooth, vertical, and concave in length. The orbits appear 

 to have been oblique and to have looked upward and forward. The 

 length of that on the left side is about 16 millimetres. The frontal 

 bone (/ ) terminates anteriorly in a forked suture, which receives the 

 ends of the nasal bones (n) in the middle, and the prefrontal bones (pf) 

 on the oblique external margins. The prefrontal bones, however, 

 are not very distinct from the nasal bones, though the suture appears 

 to run on the inner side of sharp ridges which form their inner 

 borders. But of this I cannot speak positively, as the anterior ter- 

 mination of the suture cannot be distinguished. 



These prefrontal bones (p/), or prefrontal elements of the nasal, are 

 channelled in length ; they reach backward to the orbit and are 

 about 2 centimetres loug. The exact width of the specimen in 

 front of the orbit does not represent the width of the bones during 

 life. As preserved, the width is not more than 16 millimetres. 

 During life the width may have been 2 J centimetres. The nasal 

 bones, as preserved, are 56 millimetres long. Where they join the 

 frontal elements they are about 4 millimetres wide. They attain 

 theii* greatest width where the slightly diverging prefrontal ridges 

 terminate on their sides, and are there about 9 millimetres wide 

 at rather more than a centimetre from the frontal suture. The 

 longitudinal median suture between the nasal bones is well marked 

 and wider than in the frontal region ; yet the nasal bones form an 

 elevated median keel slightly convex in length aud defined by a 

 well-marked channel on each side. The bones converge slowly 

 anteriorly and may have extended a little further than is indicated 

 by the specimen, if they terminated in a point. The circumstance 

 that the maxillary bones are not preserved is strong presumptive 

 evidence that the maxillaries were vertical, or at least formed a sharp 

 angle with the roof of the skull. It is perhaps remarkable that no 

 portion of the nasal bones can be identified as having entered into 

 the external nares, though in many Pterodactyles, such as Cyc- 

 norhamphus suevicus, there is no lateral indentation of the bones 

 in the nasal region. If we were to regard these nasal bones as 

 having extended to within an inch of the extremity of the skuU the 

 total length of the head would not have been more than 5^ inches, 

 and the toothed portion of jaw would probably not have exceeded 

 2 inches. The teeth I should infer to have been of about the size 

 of those of Cycnorhamphus suevicus of Quenstedt, which stood about 

 15 inches high. 



The characters which especially distinguish this auimal are, first, 

 the remarkable length of the roof of the skull, posterior to the orbits (o), 

 which amounts to about 38 millimetres ; so that if the orbits bounded 

 the anterior part of the cerebral region, as is usual in Pterodactyles, 



