TF. Davies — On Saurocej^halus. 261 



portions adhering to each counterpart. It is imperfect, insomuch as 

 neither the symphysis nor the articular bone are complete ; the 

 angular bone is also imperfect, and the lower marginal border is not 

 clearly defined : yet enough is preserved to enable ns to form an 

 approximate estimate as to its original size and form. The fragment 

 is 6 inches and 2 lines in length, of which, about 4^ inches was 

 occupied by the dental alveoli : at a distance of 4 inches from the 

 symphj'sis it has a vertical depth of 2 inches and 4 lines, and from 

 this point it tapers to a depth of only 10 lines at the symphysis. 

 Upon one block, and occupying a space of 1 inch and 8 lines of the 

 posterior half of the dentary margin, are preserved a consecutive 

 series of 17 entire teeth, one just emerging from its alveolus; they 

 are closely set, and gradually increase in size from the front to the 

 back, the anterior tooth being 4 lines high, and the last having a 

 height of 6 lines, the crown being 2^ lines high, and in antero- 

 posterior breadth 1 line at its base; these dimensions seem to be 

 about the relative proportions of the crown to the fang in all the 

 teeth ; they are compressed and lancet-shaped, and the enamel is 

 very finely striated. Each fang has a central shallow vertical sulcus, 

 which is continued into the base of the crown, but they are not so 

 distinctly facetted at the sides as are the teeth of Saurocejphalus lanci- 

 formis. Anterior to, and also behind this series of teeth, the alveolar 

 region of the dentary is broken, so that we cannot with certainty 

 estimate the number of teeth the mandible contained. 



Upon the counterblock are preserved the imperfect angular bone 

 and the symphysial end of the mandible, which supports the first 

 five teeth ; they are separated by a considerable interval of the 

 broken alveolar border from the other series ; these anterior teeth 

 are much smaller, the fifth, or last tooth, which is wholly exposed, 

 being but 2 lines in height. They thus agree in their relative 

 proportions with regard to the gradual increase in size of the teeth 

 from the front to the back of the mouth. The mandible is deep and 

 laterally compressed, the bones being very thin ; the articular bone 

 is compai'atively short, but its sutural margins are obscure ; it shows 

 the articular notch. A portion of a quadrate bone is present, of 

 which, little more than the articulating condyle is preserved. 



The bones of the head, as previously stated, are too fragmentary 

 and displaced for their characters to be accurately defined. 



It is with much pleasure that I dedicate this new species to my 

 friend, ' Dr. H. Woodward, F.E.S., etc., by whose exertions this 

 specimen, with many other fine fossils from the Maestricht beds 

 forming the Yan Breda Museum at Haarlem, were secured for the 

 National Collection. 



Fig. explanation OF PLATE VIII. 



1 . Inner view of the maxillary of Saurocephalus Woodwaj-di, showing the foramina 



and notches, natural size. 



2. Outer view of the left mandihular ramus of the same, drawn from the two blocks 



of matrix, natural size. 

 2a. Enlarged outer view of the anterior tooth of the posterior series, 3' times nat. size. 

 2b. Inner view of the same tooth. 



3. Proximal end of muzzle of Erisichthe Dizoni, showing the pair of rostral teeth. 



