08 
PALAEONTOLOGY OF NEW YORK. 
TABLE OF FENESTELLIDJE OF THE LOWER HELDERBERG GROUP. 
Fenestella. 
a. Simple angular branches with two ranges of cell apertures. 
F. crebripora. F. Hestia. 
F. Junceus. F. iEsyle. 
F. Oleia. F. Noe. 
F. Spio. 
b. Simple angular branches with three ranges of cell apertures just below the 
bifurcations of the branches. 
F. Althasa. F. stricta. 
F. Eudora. F. Idothea. 
c. 
Branches with prominent nodes or carince. 
F. Adraste. 
F. Sylvia. 
F. Philia. 
F. Tliyene. 
F. Coronis. 
F. Idalia. 
F. quadrula. 
F. adornata. 
d. Unitrypa, carince elevated, connected by simple bars. 
F. (U.) precursor. F. (U.) Nervia. 
F. (U.) Nervia, var constricta. 
e. Hemitrypa, carince elevated, connected by alternating bars, forming an inter¬ 
mediate false crest. 
F. (H.) biserialis. F. (H.) biserialis, var. exilis. 
/. Polypora, branches with three or more ranges of cell apertures. 
1. Branches with two and three ranges of cell apertures—three ranges pre¬ 
dominating. 
F. (P.) compressa. F. (P.) compacta. 
F. (P.) Lilsea. F. (P.) arta. 
F. (P.) obliqua. 
2. Branches with three and four ranges of cell apertures. 
F. (P.) paxillata. 
