126 



Heliophvlllm COXFLLEN8. Hall. (Fig. S.) (111. Dev. 

 Foss. Corals., PI. XXVI.) 



Distinguishing Cliamcters. — Conipoiind or confluent 

 growth, often forming heads of considerable size; strongly 

 wrinkled peritheca surrounding the colony, and the free 

 parts of individual corallites where separated; moderately 

 deep caliees; well-developed carinated septa. 



Found only in the Encrinal limestone, on the Lake Shore. 

 (Also at Morse Creek.) It is rare. 



Genus CYSTirHYLLUM. Loxdsdaee. 



[Ety. : Kiisti's, cavity; phyllon, leaf.] 

 (:Murcli. Sil. S\'St., p. 691, 1839.) 



Chiefly simple coralla, varying in outline from depressed 

 turbinate to cylindrical ; often irregular in growth. Septa 

 rudimentary and freqnenth' obsolete, the 

 floor of the calyx being formed by the upper 

 ])ortion of the vesiculate filling. Entire 

 interioi- of corallum filled with vesicular 

 tissue, disposed in more or less regular series, 

 and presenting in section a rough tabulate 

 appearance. An epitheca is present. Fre- 

 quent constrictions occur in some forms, 

 indicating periodic rejuvenation. 



Cystiphyllum coxiFOLLis. Hah. (Fig. 9.) 

 (Pal. N. Y. 111. Dev. Foss.. PL XXX., Figs. 3-9. ) 

 Distinmiisliinfi- Cliaracters. — Slender cvlin- 

 drical form; irreg-ular, intermittent o-rowth; 

 coarse wrinkled epitheca; moderate-sized 

 cysts arranged in a cup-like manner; rather 

 shallow calyx with simulation of septa by 

 the radial arrangement of the cysts. 



Found in the coral layer of the lower Moscow shales, at 

 Sections 5. 0, 7; also on the Lake Shore. Occasionally it 

 occurs in the Demissa bed. 



Cystiphyllum ameriuaxum. E. and H. (Fig. 10.) (Pol. 

 Foss. d. Terr. Pal., p. 4G4.) 



Fig. 9. Cystiphyl- 

 lum conifollis. 

 Showing the pre- 

 vaihng form and 

 irregularities 

 (after Hall). 



