CORALS AND BRYOZOA. 
23 
Ccelocaulis, n. s. g. 
Branching forms having the structure of Callopora, but growing as hollow 
steins, the thin expansion lined with a striated epitheca. 
Callopora (Ccelocaulis) venusta. 
PLATE XIT, FIGS. 20-21; AND PLATE XXIII A, FIGS. 1-3,4? 5. 
Callopora venusta, Hall. Twenty-sixth Rept. N. Y. State Mus. Nat. Hist., p. 101. 1S74. 
“ “ “ Thirty-second Rept. N. Y. State Mus. Nat. Hist., p. 155. 1S79. 
“ “ “ Report of State Geologist for 1SS2. ExSl. pi. 12, figs. 20-24. 1883. 
Zoarium ramose, hollow; diameter of branches from 3 to 5 mm.; bifurcations 
frequent. Thickness of tissue from .25 to 1 mm Inner surface a thin epi¬ 
theca with transverse wrinkles and line longitudinal striations caused by the 
recumbent portions of the cells. Cells tubular, arising from the epitheca 
and parallel with it for a short distance, then turning abruptly outward. 
Apertures oval, length .33 mm., width .20 mm. ; sometimes irregularly dis¬ 
posed, but generally in more or less regular quincunx order; frequently in 
contact: margins thin, except when thickened by silification; distinctly 
elevated. Mesopores minute, polygonal; generally only a single series be¬ 
tween adjacent apertures: margins thinner and less elevated than those of 
the apertures. The margins of the apertures and mesopores are usually 
smooth, but are sometimes ornamented by numerous minute spinules. Sur¬ 
face marked by distant, slightly elevated monticules, upon which the aper¬ 
tures are larger than on other portions. Intercellular space sometimes 
septate, at other times apparently vesicular 
This form is distinguished from C. cellulosa by its hollow branches, and its 
larger and more regularly disposed cells. 
Formation and locality. Lower Helderberg group, near Clarksville, N. Y. 
Callopora (Ccelocaulis) mediopora, n. sp. 
PLATE XIV, FIG. IS; AND PLATE XXIII A, FIGS. 11-13. 
In part Callopora parasitica, Hall. Thirty-second Rept. N. Y. State Mus. Nat. Hist., p. 157. 1879. 
“ “ “ Report of State Geologist for 1882. Expl. pi. 14, figs. 13-18. 1883. 
Zoarium ramose,branches hollow, often flattened; thickness .75 mm. Cells tubu¬ 
lar, oblique to the surface. Cell apertures oval, sub-triangular or trilobate, 
