H. G. SEELEY ON NEW SPECIES OF PEOCOLOPHON. 797 



46. On new Species of Peocolophon from the Cape Colony preserved 

 in Dr. Geieeson's Museum, Thoenhtll, Dumfeiesshiee ; with 

 some Remaeks on the Affinities of the Genus. By Haeey 

 Goviee Seeley, Esq., F.L.S., E.G.S. &c, Professor of Geography 

 in King's College, London. (Read June 5, 1878.) 



[Plate XXXII.] 



De. Thomas Boyle Geieeson transmitted to me for description 

 three more or less perfect small skulls, which all belong to the 

 genus Procolophon, instituted by Professor Owen for some small 

 reptiles from the Tafelberg. Dr. Grierson's specimens were collected 

 by Mr. Donald White from Donnybrook, Queenstown District, Cape 

 Colony. They are contained in a hard red ironstone matrix, often 

 crystalline, which is apparently concretionary, and invested one 

 skull much in the same manner as the clay-ironstone of our own 

 country often invests Carboniferous fossils. The matrix can be re- 

 moved only in part, because the bones and the cavities between them 

 are frequently filled with brittle and crystalline carbonate of lime. 

 Hence the thin film of external bone is often broken away in the 

 endeavour to develop the specimens. 



Peocolophon Geieesoni, Seeley. (PI. XXXII. figs. 1-3.) 



Of this species but one example has been found. The skull is 

 of subtriangular outline, as in many lizards ; and, as in lizards, it is 

 rather depressed and flattened above. The occipital region appears 

 to be vertical ; the eyes are a large oval, placed nearer to the back 

 of the skull than is usual in lizards, and look outward and upward. 

 The nostrils are nearly terminal, but look laterally, being divided 

 from each other by the narrow ascending process of the premaxillary 

 bones. 



In the median line, from the premaxillaries to the supraoccipital 

 region, the specimen measures 1-^- inch. The occipital region, 

 which is slightly compressed on the left side, measures from the 

 median line outward j 6 ^ inch, so that the region was probably 

 1-A- inch wide. The greatest width of the skull was attained nearly 

 at the back of the orbit, in a line passing through the foramen 

 parietale, and results from the convex bulging of the malar bones, 

 where the width may have been 1^ - inch. At the anterior corner 

 of the orbit the transverse measurement is T 6 ^ inch ; while the width 

 of the upward bars of the two premaxillary bones which divide the 

 nares is y 1 ^ inch. The upper jaw extends beyond the lower, and the 

 upper termination of the premaxillaries and the adjacent part of the 

 nasal bones are compressed so as to form a short anterior region, 

 which looks obliquely upward and forward. 



All the roof-bones of the cranium appear to be double. The 

 foramen parietale is large, rounded, and slightly elongated longitu- 



