60 CHELON1A. 



Lytoloma crassicostatum (Owen 1 ). 



Syn. (?) Testudo plana, Konig 2 . 

 Chelone crassicostata, Owen 3 . 

 Thalassochetys crassicostatus, Cope 4 . 

 Puppigerus crassicostatus, Cope 5 . 

 (?) Chelone latiscutata, Owen 6 . 

 (?) Puppigerus latiscutatus, Cope 7 . 

 Pachyrhynchus gosseleti, Dollo 8 . 

 Erquelinnesia gosseleti, Dollo 9 . 

 Euclastes gosseleti, Dollo 10 . 



Skull depressed, long, and pointed anteriorly, with only a short 

 interval between the orbits and the nares, and a gentle descent of 

 the facial profile between the orbits. Mandibular symphysis of 

 adult quite flat inferiorly. Shell with the neurals very short, and 

 their antero-lateral surfaces much shorter than the postero-lateral ; 

 and the ribs very wide and thick, and occupying the greater portion of 

 the inferior aspect of the narrow costals of the carapace. Vertebral 

 shields comparatively wide. Coracoid n gradually expanding from 

 the proximal to the distal extremity ; humerus with the head very 

 oblique to the shaft (fig. 6). 



This species was founded on the carapace No. E. 912, and it is 

 almost certain that Chelone latiscutata is specifically identical, in 

 which event that name should be adopted, since the type of Testudo 

 plana seems insufficient for certain specific determination. The 

 type mandible of the so-called Euclastes gosseleti (fig. 8) 12 agrees 

 almost precisely with that of No. 37205, and since other specimens 

 in the Brussels Museum which doubtless belong to the same form 

 show that the cranium is identical in contour with No. 37205, while 

 the carapace is of the same type as the undermentioned specimens, 

 there appears no reasonable doubt that the Belgian form is specifi- 

 cally the same as the English one. The Belgian specimens are 



1 Reptilia of the London Clay &c. vol. i. pt. i. p. 27 (1849).— Chelone 

 (Mon. Pal. Soc). 



2 Icones Foss. Sectiles, pi. xvi. fig. 192 (1825). 3 Loc. cit. 



4 Trans. Amer. Phil. Soc. vol. xiv. pt. i. p. 146 (1870). 



5 Ibid. p. 235. 



6 Rep. Brit. Assoc, for 1841, p. 179 (1842). 



7 Loc. cit. p. 235. 



8 Bull. Mus. R. Hist. Nat. Belg. vol. iv.p. 138 (1886). 



9 Geol. Mag. dec. iii. vol. iv. p. 393 (1887). 



10 Ann. Soc. Geol. Nord, vol. xv. p. 115 (1888). 



11 See Owen, ' Reptilia of the London Clay, &c.' vol. i. pt. i. pi. xiii. 



12 The writer has had the advantage of making an actual comparison with the 

 Belgian specimens. 



