72 PALEONTOLOGY OF ILLINOIS. 



unequal, generally reaching to the center where they are a little 

 curved, especially those adjacent to the septal fossette. Height 

 5 to 6 cent., diameter of the cup 2% to 3 cent. Locality, Warsaw, 

 111." 



This description corresponds well with the form described sub- 

 sequently as Z. spinulifera, the principal difference being in the 

 larger number of lamellae in E. and H.'s specimen. This charac- 

 ter, however, is a variable one, and as there is no other form 

 known from that locality that has even as many as fifty 

 lamellae, it becomes almost certain that their specimen was 

 specifically identical with that subsequently described as Z. 

 spinulifera,. 



The form from the Keokuk limestone that has usually been 

 called Z. dalei, has only about 36 to 42 lamellae, and agrees 

 well with the form described by the above named authors under 

 the name Z. centralis, to which I have no hesitation in referring 

 it. The specimen figured on PL X, figs. 12-12a, belongs to the 

 lower or Warsaw division of the St. Louis limestone, and was 

 found by the writer at Warsaw, 111. 



No. 2556 of the Illinois State Museum. 



ZAPHRENTIS CENTRALIS, Edw. and Haime. 



PI. IX, Figs. 1-la. PL X, Figs. 13-13a. 



Coral in the form of a curved cone, moderately elongated, 

 without prominent transverse ridges; cup deep, circular; septal 

 fossette large, central, and prolonged on the side of least curva- 

 ture; lamellae forty to forty-two, strongly developed and arranged 

 usually in four groups. 



Heighth of a mature specimen 3 inches; breadth of the cup 

 1% inches. A smaller specimen measures 2% inches in length, and 

 breadth of cup 1% inches. 



Position and locality: Keokuk limestone, Warsaw and near 

 Plymouth, 111. 



Collector, A. H. Worthen. 



No. 2563 of the Illinois State Museum. 



NOTE. Edwards and Haime in their description of Z. dalei, do not mention the short 

 s' incs that ma be observed on specimens that have not been weathered, but the^eare 

 oiten obliterated on specimens that have been long exposed to atmospheric influences. 



