BY E. P. RAMSAY, F.R.S.E. 159 



widest, 1^ in its length ; all are separated from one another. The 

 first wedged in between the anterior dorsal plate and first pair of 



costals, narrow 4-sided, pointed in front, sides curved, almost ovai 

 behind, becoming obsolete or anchylosed between the 5th or 6th 

 costal plate. 



The nuchal plate apparently anchylosed with the marginal and 

 costals on either side, the sutures scarcely traceable, the 1st pair 

 of marginals short, five-sided, about half as long again as wide, 

 somewhat oblong, their outer margin rounded, anterior upper 

 margin enters the outer lateral margin of the anterior plate 

 forming two sides of an angle, the other margin joining the costal 

 plate and the adjoining second marginal plate are comparatively 

 straight. 



First pair of costal plates four-sided, straight behind the 1st 

 vertebral plate except where they surround it ; greatly widened out 

 anteriorly and laterally, joining the first two marginals, and part 

 of the third where they are nearly twice as wide as on their dorsal 

 boundary, posterior margin more than three times the length of 

 the dorsal. 



Second pair of costals long, about two-thirds wider at the 

 marginal than at the vertebral boundary, fourth marginal 

 oblong, its suture opposite the hinder margin of the third costal. 



The 4th and 5th costal plates similar to the 2nd pair, but each 

 increasing in width at the junction with the marginals and 

 decreasing above on the vertebral line ; the 7th, 8th, and 9th, and 

 the adjacent half of last marginal forming a sharp dorsal ridge and 

 anchylosed together. 



Carapace subcordiform highly elevated and rounded in front ; 

 laterally flattened behind, and strongly keeled, the sides shelving 

 with the marginal shields expanding, densely rugose. The three last 

 costal plates connected along the vertebral line forming an elevated 

 sharp ridge, which extends to the centre of the pygomarginal, the 

 adjacent marginal plates expanded over the hind legs. The anterior 

 margin of fore legs covered with from 7 to 10 narrow band-like 

 oblique unequal plates (see pi. VI., fig. 1.) ; nails of the 1st 

 and 2nd toes long, whitish iv colour : other toes flattened, 



