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283 
but may be wanting, having a granulose character, an indefinite outline, 
and no central perforation; mesopores are variable in number; diaphragms 
occur in both sets of tubes. The zoaria consist of frond, ramose, massive, 
laminate and incrusting types. 
Monticulipora intersita, Ulrich and Bassler. Plate IV, Figs. 1-2. Tne 
zoarium consists of parasitic expansions, 1 to 3 mm. thick, with faintly dis- 
tinguished clusters of larger zooecia on the surface. 
The zooecia are thin walled and angular with the usual granular wall 
structure. 
The diaphragms and cystiphragms are crowded much as in M. discula 
except that the opening left by the cystiphragms is nearly always open on 
one side and subtriangular in shape. Mesopores are abundant and closely 
tabulated, having generally three diaphragms in the same distance in which 
two cystiphragms occur in the zooecial tubes. Acanthopores are wanting. 
Occurrence: Pierce limestone, Murfreesboro, Tennessee. 
Holotype: 43878, U. S. Nat. Mus. 
Monticulipora discula, Ulrich and Bassler. Plate IV, Figs. 3-4. The 
zoarium forms small discs that are attached to foreign bodies. They are 
less than 12 mm. in diameter and about .5 mm. in thickness. The zooecia 
are thin walled, angular, and nine of the average size occur in 2 mm. A 
cross-section of the cystiphragms tangentially forms large oval openings. 
The zooecial tubes are crowded with diaphragms (3 to 4in a tube diameter). 
Acanthopores are apparently wanting. Mesopores are very few and occur 
in clusters only. 
Occurrence: Pierce limestone, Morfreesboro, Tennessee. 
Holotype: (108) U. S. Nat. Mus. 
Monticulapora compacta. Ulrich and Bassler. Plate IV, Figs. 5-6. The 
colony grows into an upright ramose zoarium with compressed solid 
branches. The surface is even with maculae of the larger zooecia rather 
indistinct. 
There are eight to nine apertures in 2 mm. The wall and acanthopore 
structure is similar to the M. incompta. The acanthopores are strong, oc- 
curring at most angles of the zooecia and in various horizons within the 
axial region of the zooarium. 
Mesopores are few and scattered. 
Diaphragms and cystiphragms are closely crowded, 2 to 3 in a tube di- 
ameter in the axial region and becoming more numerous towards the sur- 
face where there are from 25 to 30 in 2 mm. 
Occurrence: Pierce limestone, Murfreesboro, Tennessee. 
Holotype; (21) U. S. Nat. Mus. 
Genus Orbignyella, Ulrich and Bassler. Genotype: Orbignyella subla- 
mellosa Ulrich and Bassler. Orbignyella Ulrich and Bassler, Smiths. Misc. 
Coll. (quart. issue), 47, 1904, p. 18. Bassler, Bull. U. S. Geol. Surv., 292, 
1906, p. 26; Bull. U. S. Nat. Mus:, 77, 1911, pp. 181, 182. 
Monticulipora (part) Ulrich, Jour. Cincinnati Soc. Nat. Hist., 5, 1822, 
lw. 153, 282; Geol. Sury. Illinois, 8, 1890, pp. 370, 407. 
