(iv) 46 



Palasontologia Sinica 



Ser. B. 



Changshania? truncata Sun (sp. nov.) 



Plate III, Figg. 3. 

 1923 Changshania truncata Sun. Bulletin of The Geological Society of China Vol. II, No. 1-2 (listed). 



This species is represented by several cranidia, free cheeks and pygidia probably 

 of this species. 



Cephalon semicircular in outline, with genal angles (of free cheeks) prolonged 

 into slender spines bending inward to the body. Glabella truncato-conical, apparently 

 smooth ; occipital furrow slightly curved and distinct ; occipital ring of uniform width 

 throughout. 



Fixed cheeks very narrow, about one half the width of the glabella at the palpe- 

 bral lobe. The facial suture cuts the frontal border slightly obliquely to the anterior part 

 of the palpebral lobe, curves around the latter and then extends outward to the postero- 

 lateral margin. Palpebral lobe long and marked by infracurving furrow^ ; postero-lateral 

 limb narrow and marked by a distinct postero-lateral furrow. 



Free cheeks and pygidia apparently of the same type as in Changshanid conica Sun. 



This species is characterized by its broad truncato-conical glabella, narrow fixed 

 cheeks and slightly curved occipital fuiTOw and the transverse pygidium with conical axis 

 and antero-lateral rounded extensions. 



This species differs from Changshania conica Sun in the broad truncato-conical 

 glabella, comparatively narrow fixed cheeks, and narrow postero-lateral limb. Its form 

 lies between Enmerichella and Changshania and I provisionally place it under Changshan'ui, 



