THE CHELONIA. 1019 
pubis is a small square bone with a foramen, and shows that the 
pelvis was plate-like. 
The femur of the type is a slender sigmoidally curved bone with 
not very well ossified ends and no very marked characters. 
The tibia and fibula stand in the specimen at right angles to it ; 
in natural articulation thei short stumps present no features of 
interest. 
Dermal bones are only shown in 49423, 
Tn this individual, in the anterior dorsal region a small patch of 
what is undoubtedly bone substance is shown lying at a con- 
siderable distance above the ribs and neural arches. This is 
clearly divided into pieces, one of which forms a small round ridge 
in the middle line. The rest of the patch shows a dividing line 
running longitudinally and a transverse division apparently 
coincident with the line where the two ribs below it meet. On 
the posterior end of the specimen, at the same distance above the 
ribs, a narrow line of bone is seen in transverse section. This 
specimen gives conclusive evidence of the actual presence of 
dermal ossifications ; but these are so incompletely preserved as to 
make any statements of their distribution of very slight value. 
There seem, however, to have been a median series nnd lateral 
rows. 
The other specimens have no matrix preserved outside the ribs, 
so that the scales cannot be seen in them. 
The chief features of the structure of Kunotosauria as shown 
by these specimens may be summarised as follows :— 
The skuli is small, with a wide basisphenoid, a palate of the 
ordinary primitive reptilian type with many teeth, teeth in the 
maxille and premaxille. The external nares are confluent, there 
being no internarial processes of the premaxille. The neck is very 
flexible and sharply marked off by its narrowness from the 
trunk. 
There are ten dorsal vertebre of a slender character with nearly 
obsolete neural spines and with rib-facets far forward on the 
centra 
The first and last dorsal ribs are of an ordinary character, but 
the remaining eight are so extremely broadened as to touch one 
another by their edges. As shown by the uncompressed speci- 
mens, particularly R. 4054, the dorsal region was strongly convex, 
and the body was nearly circular in section. 
The very small relative size of the pelvis shows that the tail 
was separated from the trunk by its much inferior diameter. 
The pectoral and pelvic girdles are of ordinary “ old- fashioned ”” 
type. 
The dorsal region is covered with dermal ossifications, of which 
there are apparently median and lateral series. 
It will be noticed that so far as the structure is known, Huno- 
tosaurus agrees exactly with the hypothetical ‘‘ Archichelone” 
arrived at by a discussion of the structure of the known Chelonia. 
