from the Middle PurhecJc of Swanage. Ai)i 



Some dimensions of this specimen are: — 



Skull (PI. VIII. fi- 1) : cm. 



lieii^tli (npprox.) 37 



Width between orbits 4*0 



„ at postfrofitals 104 



„ of tilt' middle of the snout . . . . (appiox.) li'O 

 Mandible : 



Length (approx.) 42-5 



„ of symphysis 20'5 



Length of the fused centra of atlas and axis 4-2 



Dorsal vertebra : 



AVidth of cent rum 2'o 



Height of centrum 2'o 



„ to top of neural spine 7'0 



Length of humerus \2-^ 



„ ulna 8-;{ 



tibia n-I 



fibula 10-9 



AVidth of a dorsal scute (PI. VIII. fig. 2) 11-7 



Length of a dorsal scute 4-1 



Tlie collection also includes the posterior portion of a skull 

 (PI. Vlir. fig". 3) of a P/iolidosaurus apparently specifically 

 ditFerent from P. decipiens. The chief points of difference 

 are : (1) the complete absence of sculpturCj and (2) the form 

 of the anterior region of the fi-ontal ( /V.), which, instead of 

 forming a broad wedge thrust between the iiinder ends of the 

 nasals, seems to have extended as a narrow strip between 

 these bones, which furthermore ran a little further back than 

 in P. decipiens. This species, which is from the same horizon 

 and locality, may be called PhoHdosaurus Icevis, sp. n. 



The form of the skull and position of the sutures will 

 be best understood from the figure of the type specimen 

 (PI. V 111. fig. 3). 



Some dimensions (in centimetres) of this specimen are : — 



Length from supraoccipital to top of frontal lo-4 



„ of temporal fossa 3-9 



Width at postfrontals 11-2 



Least width between orbits 4-0 



From the above account it will be seen that Pholido- 

 saio'HS is distinguished by the relativ^ely small size of the 

 suprateniporal fossa, which are little larger than the orbits, 

 the long narrow snout on wliich the nasals meet the facial 

 processes of the premaxillop, the internal nares far back, 

 but still closed below by the palatines only. The vertebrse 

 are amphicoelous. The fore linib is relatively large^ and was 



