IN THE UAIINXVOIIOUS JJlNOCJiirUALlAN REM-lLEi, 



077 



The aiiguliir is ;i very rouuirkably constfucfcud buiiu. A Utile 

 in front of the middle region of the jaw the anterior end of the 

 bone is wedged in between the splenial and tlie dentary, and on 

 passing backwards we find tlie angular becoming steadily larger. 

 As seen in the figures given, it forms most of the outer side of 

 the back half of the jaw. On the inner side of the jaw it foi-ms 

 i\. relatively small part, being largely hidden by the prearticular. 

 The very peculiar structure of the bone cannot be readily seen 

 except in section. It consists in the posterior part of the bone 

 being s[)lit in two, and containing a large cavity between the two 

 portions. 



The coronoid is relatively a very small bone, so small that it 

 might be spoken of as rudimentar3\ It lies above the anterior 

 part of the prearticular, as can be seen in text-figs. 11 ct 12. It is 



Text-figure 11. 





Eight maiidililc of tUaxosucIius cloctci BrOoni. Sliglitly lurgor lliaii ] iia(. si/.c. 



SO fragile that its anterior and posteiior limits cannot be clearly 

 made out, the delicate bone being crushed and crumpled. I'hat 

 a small coronoid is present is beyond doubt, and its limits must 

 be very nearly those shown in the figure. 



The prearticular is a long, slender bone which rur.s forward 

 from the articular to about the middle of the jaw. It forms the 

 lower border of the long, narrow opening into the jaw. In front 

 it lies between the coronoid and the splenial. Its mode of 

 attachment to the articular and to the angular will be understood 

 from the sections given. 



The sunmgular is a well-developed bone which forms the 

 upper part of the posterior third of the jaw. Anteriorly it passes 

 forwards between the deiitary and the coronoid and ])rearticular. 

 The specimen does not clearly show how much of the potjteiior 

 part is surangular and how much articular. Not improbably, 

 all the posterior strongly -developed ridge is surangular, and the 

 articular is entirely internal to it. Its relations \\ith the other 

 elements are clearly seen in the sections. . , 



Piu)C. ZooL. Soc'.— 1928, No. XLV. 45 ■ 



