62 PROCEEDINGS OE THE GEOLOGICAL SOCIETY. [Apr. 20, 



and Pisces ' in the Museum of the Royal College of Surgeons, 4to, 

 1854, pp. 97-106, there is a specimen, consisting of a portion, 

 2| inches in length, of a symmetrical pair of bones, each of a sub- 

 trihedral form, and joined together by the flattest of their sides. The 

 description which I then gave of this fossil is as follows : — " Each 

 bone increases in vertical, and decreases, but in a less degree, in 

 transverse extent, the bones becoming more closely and extensively 

 united together as they extend forward. Posteriorly, each bone is 

 grooved near the middle of its inner flattened side, the grooves, when 

 coadapted, forming a canal answering to that in a similar position 

 on the elongated symphysial part of the lower jaw of the Gavial. At 

 the opposite end of the fragment this canal is reduced to a fissure. 

 The groove which divides the two bones, both above and below, at 

 the back part of the fragment, contracts to a linear fissure as the 

 bones advance and become more united together. The result of an 

 extensive series of comparisons is, that the symmetrical bones in this 

 remarkable fossil most resemble in shape the coadapted elongated 

 dentary elements of the lower jaw of the Gavial and Teleosaurus : but 

 they show no traces of alveoli, and, if they be parts of those bones, 

 indicate a reptile either edentulous or with the teeth confined to 

 the anterior extremity of the jaw " (p. 106). 



The subsequent discovery of the fore end of the jaw of the Gavial- 

 like reptile Cynochampsa adds to the probability of the above con- 

 jecture. 



Vertebrae of Saurians from the same deposits of the Drakenberg 

 afforded characters of the genera Massospondylus, Pachyspondylus, 

 and Leptospondylus, which characters are given in detail in the 

 volume above cited, and were further illustrated by figures and dia- 

 grams in my Lectures on Fossil Reptilia, delivered at the Museum of 

 Practical Geology in 1858. 



EXPLANATION OF PLATES I. II. & III. 

 Illustrative of Reptilian Remains from South Africa. 



PLATE I. 



Fig. 1. Side view of the skull of Oudenodon Bainii, one-half nat. size. [In the 



British Museum.] 

 Fig. 2. Side view of the skull of Ptychognathus verticalis, one-half nat. size. 



[In the British Museum.] 

 Fig. 3. Side view of the skullof Ptychognathus declivis, one-half nat. size. 

 Fig. 4. Back view of the skull of Ft. declivis, one-third nat. size. 

 Fig. 5. Top view of the cranium of Pt. declivis, one-third nat. size. [In the British 



Museum. Some distorted and dislocated parts have been restored in the 



figures ; the letters and figures are explained in the text.] 



PLATE II. 



Fig. 1. Side view of the skull of Galesaurus planiceps, showing the socket and 

 part of the base of the upper canine, c, and the lower incisors. 



Fig. 2. Opposite side of the same skull, showing the base of the upper canine, c, 

 in situ, and the upper incisors. 



Fig. 3. Upper view of the same skull. 



Fig. 4. Back view of the same skull. 



