334 Prof. H. G. Seeley on Euskelesaurus Brownii. 



extension backward of the proximal articular surface, the 

 large amount of vertical motion upon each other indicated by 

 the forms of the articular ends of the bones, and the strong 

 development of ligamentous surfaces. The smallest phalange 

 preserved is 1| inch long and about If inch wide at the 

 distal end. 



Claw-Phalanges. (Fig. 5.) 



The claw-phalanges are more distinctive of Euskelesaurus 

 than the other bones of the digits, though perhaps they con- 

 form most nearly to the type of Dzmodosaurus, with which 

 the other phalanges are also best compared. There are indi- 

 cations of four which progressively decrease in size, but are 

 marked by a transverse width at the proximal end which is 

 almost equal to the vertical depth. The fragment figured by 

 Fischer (I. c. pi. x. fig. 7) gives an imperfect idea of the form 

 of the claw. In the largest bones, including the Paris frag- 

 ment and the largest nearly perfect claw belonging to 

 Mr. Brown, the bone is higher than wide at the proximal end. 

 In the latter specimen the dimensions are 1\ inches high by 

 2^ wide near to the articular surface, but the articular surface 

 itself is only If inch deep and nearly 2 inches wide, o wing- 

 to the way in which the superior margin of the bone descends 

 and indicates a strong ligamentous attachment towards the 

 point from which the first measurement is taken. The 

 superior surface of the phalange is strongly inflated, very 

 convex from side to side, and also convex from behind 

 forward. The sides of the bones are characterized by deep 

 grooves, which divide the lateral surfaces by their arched 

 contour into a smaller inferior and a larger superior portion. 



The base is comparatively flat, being only gently convex 

 from side to side and moderately concave in length. The 

 form combines the height of the Megalosauroid claw with 

 almost the width of the Iguanodont claw, and is therefore 

 mere massive than either. But the extremity of the claw is 

 not so much recurved as in Megalosauroids. The largest 

 specimen is imperfect at the extremity and measures 4 inches 

 long in greatest extent, and was probably half an inch longer ; 

 so that it is less than twice as long as deep. A smaller 

 specimen is fully 3| inches long and more than 2 inches deep. 

 The smallest specimen is much more slender, 3j inches long 

 and about If inch deep. As already indicated, the depth of 

 the bone at the articular end slightly exceeds its width, 

 though the depth of the articulation is always rather less 

 than its breadth. It seems probable that the ungual phalanges 

 decreased in size, as in Dimodosaurus } in passing from the 



