299 
The zoarium consists of a narrow, bifoliate, branching frond or cribrose 
forms, with a pointed base, articulating with a small basal expansion ; 
apertures subcircular, surrounded by a peristome subpolygonal in out- 
line ; interspaces depressed, usually with one or two fine tortuous elevated 
lines. 
Graptodictya fruticosa n. sp. Plate XII, Figs. 1-2. Zoarium consists of 
bifoliate branching frond, 1 to 1.5 mm. wide. The branches rise perpendic- 
ularly from the margins and are irregularly spaced from one another. On 
the type specimen the distance between the branches varies from .1 mm. 
to 1.5 mm. and portions of the zoarium can be selected in which 4 stipes: 
spring from one margin and one from the opposite margin in the space of 
5 mm. Some of the branches develop and bifurcate similar to the principal 
stipe and others form short lateral extensions 1 to 3 mm. in length. The 
bushy effect resulting from the irregular branching was observed in a 
number of specimens, with similar internal characters, and is here consid- 
ered of specific value. 
Sections show that the apertures are oval, arranged in longitudinal series 
and separated by two fine tortuous lines. Fine zooecia occur in 2 mm. within 
the series. At the bifurcation, the striated appearance is increased by 
the presence of narrower apertures; the serial arrangement is less definite, 
and the fine tortuous lines occasionally wind diagonally among the zooecia. 
The primitive tubes are thin-walled and lie upon the median laminae 
from the proximal end to the hemiseptum, where the outward turn is short 
and sufficient to permit the tube to approach the surface perpendicularly. 
Diaphragms, mesopores and median tubuli are wanting. 
The hemisepta is short, blunt, and projects directly towards the meso- 
theca. 3 
The form of the zoarium distinguishes this species from others of the 
genus. 
Oceurrence: Pierce limestone, Walter Hill, Rutherford County, Tennessee. 
Holotype: 2387-12. Indiana University. 
Graptodictya dendroidea n. sp. Plate XII, Figs. 3-4. The zoarium forms 
a narrow bifoliate frond, 1.5 to 2 mm. wide. The first, 10 to 15 mm. above 
the articulated base, is an wnbranched stipe above which dichotomous 
branching occurs every 2.5 to 3 mm. 
The zooecia are oval, arranged in longitudinal rows, 8 to 9 in 2 mm. 
Two fine lines separate the rows in the middle of the lateral surface, but 
near the border where the long axes of the apertures are obliquely directed 
the tortuous lines pass between the apertures in the series. The walls of 
the zooecia in G. fruticosa are thinner, the apertures larger and the longi- 
tudinal rows (14 to 14.5 in 2 mm.) more closely crowded than in G. 
' @endroidea (13 to 13.5 in 2 mm.). 
The form of the zoarium of G dendroidea is characteristically different 
from all other described species. 
Occurrence: Pierce limestone; Walter Hill, Rutherford County, Ten- 
nessee. 
Holotype: 287—13, 14. Indiana University. 
