430 OLIVER p. HAY 



figure of it is presented (fig. 9). Beginning at the rear, there is 

 found on the right xiphiplastral (e) a thin plate of bone now 30 

 mm. long and 10 mm. wide, but it was evidently once 6 mm. 

 longer. The greatest thickness is 3 mm. On the left side this 

 bone is missing, but the surface to which it was articulated is 

 distinct. These bones, as in other cases, are situated at the 

 center of growth of the corresponding scutes. Coming forward 

 to the femoral scutes, it is found that nearly the whole of the 

 outer border of each is occupied by two epithecal bones {d, d). 

 One of these lies on the xiphiplastral, the other on the hypoplas- 

 tral; but on the left side the hinder of the two bones has scaled 

 off. The length of the two bones is 62 mm. ; the breadth 11 mm. 



Along the hinder border of the right abdominal scute, at the 

 lower end of the bridge (c), there is a thin bone 22 mm. long, 10 

 mm. wide, and 4 mm. thick at the hinder end. On the left side 

 there is no corresponding bone, but a small scar marks its posi- 

 tion. On the hinder border of each pectoral scute at the upper 

 end of the bridge (5, h) is a large plate of bone, the length being 45 

 nrni., the width 20 mm., the greatest thickness 5 mm. At the 

 outer hinder corner of the humeral scutes there is hardly any 

 indication of the epithecal bones that might be looked for there. 

 On the right side is a rough surface where the little plate was 

 probably once seated. On the gular of each side is a rough sur- 

 face where evidently a plate of bone was once attached. The 

 scar on the right side is 20 mm. long and 11 mm. wide; the one 

 on the left side is narrower (a, a). 



One might expect to find some evidences of the presence of 

 an epithecal bone within the area of the intergular scute, but 

 none is certainly found. From the plastron of no. 6596 most of 

 the epithecal bones have been lost. Those on the femoral scutes 

 were not so large as in no. 1167. On the abdominal scute areas 

 traces of them are mostly gone. On the pectorals the epithecal 

 bones are large. On the right side the bone is missing, but there 

 is a deeply pitted surface where it was lodged. On the left side 

 the bone consists of two pieces, the intermediate part having 

 probably been absorbed. The two pieces taken together measure 

 38 mm. in length; the rear piece is 23 mm. wide. The borders 



