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phery, closing the mesopo.es 4.ud rounding the apertures of the zooecia. 
Two to three diaphragms oecur in the zooecia of the mature zone in the dis- 
tance of one-tube diameter. 
Many of the characters of H. palera are very similar to H. microstigma 
from the Richmond, but the much less number of acanthopores and the 
absence of inflections of the zooecial walls by the acanthopores in H. patera 
serve to differentiate them. 
Occurrence: Pierce limestone: 2 miles northwest of Murfreesboro, Ten- 
nessee, at Stokes Gannon’s ford. 
Holotype: 242-4. Indiana University. 
Heterotrypa stonensis n. sp. Plate VIII, Figs. 1-2. Zoarium ramose; 7 to 
15 mm. in diameter. The surface is smooth; monticules are absent; small 
inconspicuous maculae of clusters of large zooecia are numerous, .2 to .5 
mm. across and 2 to 2.5 mm. apart, measured from center to center. 
The zooecia are thick-walled, and subcircular. A completely developed 
cingulum is present in each zooecia. The true zooecial wall is angular, 
finely granular, amalgamated and separated from the cingulum by a distinct 
dark line of contact; 8 to 9 zooecia oceur in 2 mm. 
The acanthopores are of medium size, with indefinite boundary; 2 to 3 
about each zooecia. The central lumen is very small and mostly indistinct. 
Mesopores are very few, being absent in most of the tangential sections. 
The zooecial tubes in the immature region are thin-walled and crossed 
by very few diaphragms. They turn outward in a slight curve to the initial 
mature region where the bending is subangular and short. Thruout the 
deep mature zone the tubes proceed directly to the surface. 
Diaphragms in the mature region are spaced about one-fourth to one-half 
tube diameter apart. Coalesced and infundibular diaphragms are present. 
The scarcity of diaphragms in the axial region, the thinner cingulum and 
inconspicuousness and zooecial composition of the maculae of Heterotrypa 
stonensis separates it from H. patera. 
The greater abundance of acanthopores, presence of numerous dia- 
phragms in the axial region and the well developed maculae of H. micros- 
tigma distinguish it from H stonensis. 
Occurrence: Pierce limestone; two miles northwest of Murfreesboro, 
Tenn., at Stokes Gannon’s ford. 
Holotype: 242-5. Indiana University. 
Family Constellaridae. Ulrich. 
The zooarium is ramose, frondescent, laminar or inerusting. The stellate 
maculae is probably the most obvious character of this family but greater 
importance is assigned to the granular wall structure in the mature region, 
and the presence of hollow spines or granules which occur in the place of 
true acanthopores. Mesopores are angular and usually abundant. 
venus Constellaria Dana. Genotype: Ceriopora constellata (Van Cleve, 
M. 8.), Dana. Constellaria Dana, Zoophyta, 1846, p. 537. Edward and 
Haime, Mon. d. Polyp. Foss. d. Terr. Pal. (Arch. Mus. d’Hist. Nat., 5), 
