kronobavrus queen slandicus. 
As long ago as 18715 John Phillips pointed out that isolated femora and 
humeri were not always easy to distinguish. With a complete hone, distincti\e 
diagnosis is usually gained from the contours of the distal region. 
Dimensions of fragments : — 
Left humerus, 480 mm. in length to fracture. 
Maximum antero-posterior diameter of head (very incomplete), 234 mm. 
Maximum diameter across head and trochanteric buttress (abraded), 292 mm. 
Diameter of shaft, taken ten inches from proximal surface, 200 mm. , 
circumference, 585 mm. 
The contour of the shaft near the region of fracture is somewhat 
oval, indicating the usual compression of the distal region. 
Right humerus, 340 mm. in length to fracture. 
Maximum antero-posterior diameter of head (abraded), 281 mm. 
Maximum diameter across head and trochanteric buttress, 275 mm. 
Owing to the differential abrasion the diameters of the head are markedly 
different in the two specimens, but this is obviously due to bad preservation. 
In the second or shorter fragment the antero-posterior contours of the head 
appear to be almost complete, and the maximum diameter is 281. 
In so far as comparisons may be made, the measurements of the long 
bones of Kronosaurus queenslandicus slightly exceed those tabulated for 
Meijalneusaurus rex by Knight (loc. cit.). The length of the complete humerus 
of the Wyoming specimen was 991 mm., and if the robustness of the Hughenden 
limb-bones was also reflected in their length the complete bone of Kronosaurus 
exceeded a metre. 
In these Hughenden bones the convex articular surfaces slope outwards 
and downwards towards the massive buttress of the trochanter, which is 
centrally situated on the main axis of the bone and forms a projecting ridge. 
The contours are shown in Text-figures 1 to 4, but it should be emphasized 
that, owing to prolonged abrasion, the dorso-ventral diameter of the head in 
the longer specimen, or left humerus, is considerably greater than that of the 
convex articular surface in its antero-posterior extent. In the shorter specimen, 
or right humerus, where the abrasion has been more uniform, the two diameters 
are subequal. 
When viewed from above the massive trochanteric process is almost 
quadrangular, owing to the pronounced projection of its upper part, below 
which it slopes sharply away on the external surface, subsiding into the sub- 
circular shaft. 
In his first description of Plesiosaurus trochanter ius, 9 subsequently 
transferred to the genus PUosaurus , 5 6 7 Richard Owen pointed out that the long 
5 1871: John Phillips, Geology of Oxford, p. 362. 
6 1839 : R. Owen, Rep. Brit. Assn., p. 85. 
7 1861 : R. Owen, Mon. Foss. Rept,., Kimmeridge Clay, p. 7. 
