NORTH AMERICAN LATER TERTIARY AND QUATERNARY BRYOZOA. 103 



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Occurrence. — Miocene (Yorktown formation) : Yorktown and 3 miles southwest 

 of Petersburg, Virginia (common). Miocene (Duplin marl) : Wilmington, and other 

 localities in North Carolina (common) ; Darlington, Muldrows Mills, 5 miles south 

 of ^laysville, and other localities, South Carolina (rai'e). Pliocene (Caloosahatchee 

 marl) : Shell Creek, De Soto County and Munroe County, Florida (common) . 

 Pleistocene: Simmons Bluff, Yonge's Island, Charleston County, South Carolina 

 (rare); Mount Hope, Panama Canal Zone (rare). Pleistocene or Recent: Vero, 

 Florida (rare). 



Habitat. — Gulf of Mexico off Florida (21-56 meters), Tortugas (29 meters), 

 Bermuda, St. Thomas, St. John, and perhaps at Malacca (Levinsen). 



Plesiotypes. ~Ca.%. Nos. 68547-68553, U.S.N.M. 



STVLOPOMA PROJECTA, new species. 



Plate 45, fig. 6. 



Description. — Zoarium incrusting. Zooecia distinct, separated by a furrow, 



regularly oriented, sub-rectangular; frontal convex and garnished with nmnerous 



tremopores. Aperture small, transverse, with a small, narrow rimule; rounded 



at its extremity; peristome thick, salient, smooth. A small oral avicularium with 



pointed and very salient "beak is adjacent to the rimule and to the aperture. The 



ovicell is enormous, globular ornamented with tremapores; it hides the aperture. 



The interzooecial avicularium is large, convex, with rounded and somewhat enlarged 



beak. 



,, .Ax fAa = 0.10mm. „ ■ fi2 = 0.50-0.55 mm. 



Measurements. — Aperture{, „,, Zooeciai, _ „_ „ .. 



^ ita. = 0.11 mm. Ii.3 = 0.30-0.40 mm. 



Affinities. — This species is very well characterized by its small oral avicularium 

 arranged to the right or to the left of the rimule, an arrangement not observed in 

 other known species. 



Occurrence. — Pleistocene : Mount Hope, Panama Canal Zone (rare) . 



Plesiotype.— Cat. No. 68554, U.S.N.M. 



STYLOPOMA MAGNIPOROSA, new species, 



Plate 47, fig. 4. 



Description. — The zoarium is bilamellar. The zooecia are large, elongated, 



distinct, separated by a furrow, elliptical; the frontal is convex and perforated by 



large expanded tremopores. The apertura is elongated; the anter is orbicular and 



very large; the poster is formed by a small narrow rectilinear rimule; the peristome 



is thick, little salient, smooth. On each side of the apertura there are two triangular 



oblique avicularia with the beak directed towai-d the base. The ovicell is enormous, 



globular, placed on the distal zooecium, covering and hiding the aperture. 



,, , * . [Aa = 0.20mm. „ . fi2 = 0.60-0.70 mm. 



Measurements. — Apertura , „,, Zooecia , r^A- r^,-r. 



^ lte = 0.1onim. | tz = 0.4o-0.50mm. 



Affinities. — This species differs from Stylopoma isabelleana D'Orbigny in its 

 large frontal tremopores and in the beak of the avicularia directed toward the base. 

 We have observed a giant aperture corresponding probably to a special or abnormal 

 mandible. 



Occurrence.— Miocene (Bowden horizon) : Santo Domingo. 



Holotype.—C&t. No. 68555, U.S.N.M. 



