(i) 12 Palteontologia Sinica Ser. P> 



bring common species to light, and demonstrate the correspondence of the Yehli lime- 

 stone series to one or the other of the formations in the more northern region. When 

 such new material is obtained, it will be described in further numbers of this publication. 



DESCRIPTION OF SPECIES 



Class ANTHOZOA 



Family ARCH^EOCYATHINAE 



Genus ARCH/EOCYATHUS Billings 



(Subgenus Archccoscyphia Hinde) 

 Archaeocyathus (Archaeoscyphia) chihliense Grabau (sp. nov.) 



Plate I Figs. 1-3 



Caliculum irregularly sub-conical, apparently expanding in a uniform manner. 

 Basal portion unknown. Adult portion sub-circular to sub-oval in transverse section, the 

 latter possibly accentuated by compression in some specimens. Septate portion (thecarium) 

 thick, enclosing a hollow calicular cavity which, in the subcylindrical specimens, has a 

 diameter something over one third the diameter of the entire caliculum. This cavity is 

 well defined by the inner ends of the main septa, which attain a uniform length, but are 

 not bounded by any definite inner wall, or endotheca. Outer wall or exotheca formed by 

 the thickening of the outer ends of the septa, and their irregular confluence, the result 

 being a very porous wall. 



Septa thin, formed apparently by a series of small confluent trabeculre, this re- 

 sulting in the production of thin radial plates of a very porous nature, so that in transverse 

 section they appear as disconnected trabecuke, disposed in radial lines. They are very 

 numerous and arranged in groups of three or four each, the groups being separated by 

 interspaces which are about twice as wide as the interspaces between the adjoining septa 

 of a group. Occasionally one of these broader interspaces is occupied by a short septum 

 in the peripheral region. 



A section 28 mm. in diameter (PI I fig. 3), shows about 33 groups of septa, 

 making a total of from 100 to 120 septa. The specimen from which this section is cut 

 appears to have had a somewhat flaring outer edge to its calyx, a section of this showing 

 on one side, because of slight obliquity of the cut. In this outer portion the septa are 



