46 CHELONIA. 



This specimen agrees closely with the next, and its resem- 

 blance to the type is so marked as to leave no reasonable 

 doubt as to its specific identity. In this example the 

 azygous occipital shield extends forwards so as to separate 

 the two paroccipitals for a considerable portion of their 

 length, although they are in contact anteriorly. 



BowerhanTc Collection. Purchased, 1865. 



25610. The somewhat imperfect cranium of a young individual ; 



{Fig.) from Sheppey. Figured by Owen in Dixon's ' G-eology 

 of Sussex,' pi. xiii. figs. 1-3, and also in his ' History 

 of British Fossil Reptilia,' Chelonia, pi. xxv. figs. 1-3, as 

 Ohelone convexa. There is not the slightest evidence for 

 associating this cranium with the carapace on which the 

 latter species was founded. Both in this and the preceding 

 specimen the ridges on the palate are much less prominent 

 than in adult crania. The other specimen figured by Owen 

 under the same name is noticed on page 65. 



Dixon Collection. Purchased, 1851. 



30525. An imperfect and somewhat larger immature cranium : 

 from Sheppey. The contour of the epidermal shields is 

 the same as in the two preceding specimens. Purchased. 



35696. An entire cranium agreeing in size with the preceding ; from 

 Sheppey. The general contour is well preserved, but the 

 palate can be only partially cleared from matrix, and the 

 boundaries of the epidermal shields are not shown. 



Purchased, 1859. 



38959. An imperfect cranium; from Sheppey. This specimen, 

 which is nearly of the same size as the preceding, shows 

 the palate fairly well, but has lost a great part of the 

 frontal aspect. BowerhanTc Collection. 



R. 1476. An imperfect cranium, partly concealed by matrix : from 

 Sheppey. The lateral region of the right half of the 

 palate is exposed. No history. 



B. Species founded on shells. 



It is probable that the two undermentioned forms are respectively 

 identical with A. breviceps and A. cuneiceps, but there is at present 

 no evidence to connect the shells with the skulls. 



