Maryland Geological Survey 301 



Zaphrentis keyserensis n. sp. 

 Plate XIX, Figs. 1-4 



Description. — Corallite simple, conical, slightly curved, diameter in- 

 creasing slowly near apex, more rapidly above this point for a short dis- 

 tance and then slowly towards calyx. Exterior annulated by pronounced 

 constrictions placed at irregular distances ; striated longitudinally by 

 septal furrows. Calyx not observed. Primary septa 35 to 40 in specimen 

 25 to 30 mm. in diameter, most of which do not reach center. A few rudi- 

 mentary septa are present, alternating with the primary. Tabulae numer- 

 ous, close. 



Diameter of largest individual observed, 30 mm. ; length, 80 mm. 



This species approaches Z. rwineri. It differs in attaining a much 

 larger size, in being scarcely curved, and in its less conspicuous secondary 

 septa. 



Occurrence. — Helderberg Formation, Keyser Member. Keyser, 

 West Virginia, in Favosites helderhergice var. prcecedens zone. 



Collection. — Maryland Geological Survey. 



Family CYATHOPHYLLIDAE 



Genus CYATHOPHYLLUM Goldluss 



Cyathophyllum clarki n. sp. 

 Plate XIX, Figs. 5-9 



Description. — Corallite simple, conical, nearly straight or slightly 

 curved, increasing more rapidly in diameter near apex: becoming nearly 

 cylindrical near calyx. Theca annulated by tine striae and more remote 

 constrictions, constrictions deep in some eases. The weathered individuals 

 have longitudinal furrows which mark position of septa. 



Calyx not quite as deep as wide, its base concave, its sides ascending or 

 nearly erect, diameter of calyx increasing near margin. Septa about 50 to 

 GO, primaries reaching center, secondaries not quite so long. Cross- 

 section shows septa as regular radiating lines, primaries reaching center, 

 secondaries a little tliinner and shorter tlian the i)rinuiries, the space 



