Plate 37 



Page 



Fkjures 1-3. Endoceras ceritrotubulatutn, new species 62 



1, 2, Lateral view and the cross section along the upper 

 part of the specimen showing location and size of 

 siphuncle and endocones. 



3, A vertical section of the lower part of the same speci- 

 men in a lateral direction across the conch, showing 

 the sti'ucture of the siphuncle. 



Ordovician: Near Han-chung-fu, Shensi, China. 



4,5. Cycloceras (?) s7ie«stejise, new species 7J 



5, A lateral view of the holotype showing annulations. 



4, A segment of the upper part viewed from beneath, 

 showing location and size of the siphuncle. 



Formation and locality same as preceding. 



144 



