1855.] OWEN PURBECK REPTILES. 



123 



2. Notice of sotne New Reptilian Fossils from the Purbeck 

 Beds near Swanage. By Prof. Owen, F.R.S., F.G.S. 



Having received from Mr. W. R. Brodie, i'art of the right ramus 

 of Swanage, a second collection of fossils of the Lower Jaw with 

 from the Purbeck beds at Durdlestone Bay teeth of Saurillus 

 for examination, I find amongst the Ver- obtusus, Owen. (Nat. 

 tebrate specimens some IchthyoUtes and size and magnified.) 

 two examples of Reptilia : the latter seem <^«-ujaa.ii 



worthy of a woodcut ; they are small, and 

 may be described as follows : — 



Specimen A, from the "dirt-bed*," 

 no. 93 in Mr. Austen's stratigraphical 

 listf. It indicates a Lacertian genus and 

 species, for which I propose the name of 

 Saurillus obtusus. This lizard is repre- 

 sented by the right dentary bone of the 

 lower jaw (see fig.), containing 13 mode- 

 rately long, conical, blunt-pointed teeth, «. One of the teeth magnified. 



differing in form from those of the Nu- 



thetes and Macellodus described in a former communication J, and 



from the same formation and locality. 



The teeth in Saurillus are not so long nor so recurved as in Nu- 

 thetes, nor are they compressed as in that genus ; and they are not 

 broad and flat as in Macellodus. On the outer side of the dentary 

 bone are six nervo-vascular foramina in a longitudinal row, relatively 

 as numerous and large as in the Iguanodon, and indicating, as in that 

 and other Saurian reptiles, the scaly covering of the jaws and the 

 equally reptilian condition of the salivary apparatus in the little Sau- 

 rillus. Supposing the fossil to have come from a mature individual, 

 the size of the animal must have been equal to that of the common 

 European lizard Lacerta agilis. It was most probably insectivorous. 

 The specific name refers to the obtuse termination of the muzzle, as 

 indicated by the form of the fore part of the jaw, and also to the 

 blunt apices of the conical teeth. See figure. 



Specimen B, from the same bed, is a portion of jaw with two long, 

 slender, recurved, pointed teeth, of an almost circular transverse 

 section, with two opposite low but sharp ridges along the enamelled 

 crown, like those in Teleosaurian teeth. If this fragment formed 

 part of a full-grown animal, it indicates a species of Saurian, probably 

 Lacertian, reptile, distinct from any of the before-defined kinds from 

 the Purbecks. The jaw-bone is, however, too much mutilated at 

 the base of the teeth to determine their precise mode of attachment. 

 The teeth are black, with the enamel unusually lustrous. 



A portion of a jaw of a somewhat larger reptile, with empty sockets 

 for simple teeth like those of a Crocodile, is imbedded in the same 



* See also Quart. Journ. Geol, Soc. No. 40, p. 423 and p. 482. 



t Guide to the Geology of Purbeck. 8vo. 1852. 



t Quart. Journ. Geol. Soc. June 1854, no. 40, pp. 420-426, figs. 1-8. 



