PURBECK FORMATION. 33 



Genus — Saurillus,* Owen. 



Saurillus obtusus, Owen. 



The fossils upon wliicli the above genus and species were foundedf were 

 transmitted for my determination, in 1854, by Mr. W. R. Brodie, of Swanage, 

 and were discovered by that persevering explorer of the Purbeck beds, in the 

 "Dirt-bed," No. 93, of Mr. Austen's ' Stratigraphical List' above cited. 



The most instructive specimen consisted of the right dentary element of the 

 lower jaw, containing thirteen teeth. These are moderately long, conical, and 

 obtuse; but are neither so long nor so recurved as in NutJietes, nor are the 

 crowns compressed, as in that genus. On the outer side of the dentary bone, not 

 far below the alveolar border, are six nervo-vascular foramina in a longitudinal 

 row, relatively as numerous and large as in Iguanodon, and indicating, as in 

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

 reptilian simple and subdivided condition of the salivary apparatus in Saurillus. 

 The teeth are implanted according to the pleurodont type. 



Supposing the fossil to have come from a mature individual, the size of the 

 animal must have been nearly that of the common European lizard, Lacerta 

 agilis. It was most probably insectivorous. The specific name, " ohtasiis," 

 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. 



G^<:';i?/5— Macellodon,! Owen. 



Macellodon Brodiei, Owen. Tab. VIII, fig. 10. 



In the slab of the fresh-water Purbeck stone containing* the portions of upper 

 and lower jaw, with teeth, on which the above genus and species were founded,^ 

 there were also specimens of small, subquadrate, pitted, dermal scutes, and of 

 a vertebral neural arch, corresponding proportionally in size vjrith the teeth. 



One specimen consists of the right superior maxillary bone, containing eight 

 nearly entire teeth, and showing the places of attachment of thirteen or fourteen 



* Abbreviation of anvf)os, counts, a lizard. 



t 'Quarterly Journal of the Geological Society,' No. 40, pp. 423 and 482. 



X MuiceWa, a spade, vhovs, a tooth. 



§ ' Quarterly Journal of the Geological Society,' 1854, p. 422. 



5 



