Vol. I. C. C. Yii—Ordovician Cephalopoda of Central China (ii) 67 



The septa are very closely arranged. The septal distance is about 1.3 mm. at 

 the initial portion and very slightly increases to 1.8 mm. at the upper part of the frag- 

 ment. The septa are more separated along the convex side than on the concave. The 

 cameras have been filled with white calcite, but the siphuncle is completely empty, ex- 

 cept for the mud filling. 



The test is rather thick, being about 0.5 mm. Its surface is covered with 

 transverse strife, which are very fine. 



Horizon AND Locality: Same as Discoceras eurasiaticum Freeh, with which the 

 present specimens are associated. (J. S. Lee Collector). 



