NORTH AMERICAN EARLY TERTIARY BRYOZOA. . 345 



STEPHANOSELLA ENTOMOSTOMA Reuss, 1847. 



Plate 85, figs. 19-21. 



1S47. Cellc/iora cntoiiittstoma REUSS, Die fossilen Polyparien des Wiener Tertiarbeckens, 

 Haidinger's naturwissenschaftliche Abbandlungeu, vol. 2, p. 92, pi. 11, fig. 7. 



1M14. L< in-alia cntoinostoma REUSS Zur Fauna der deutschen Oberoligocans, Sitzuugsberichte 

 der U. Akademie der Wissenschaften, vol. 50, p. 27, pi. 13, fig. 6. 



1874. Lepralia cntomostoma REUSS, Die fossilen Bryozoen des Ocsterreichisch-Ungarischen 

 Miocans, vol. 1, pi. 17, p. 4, fig. 11. 



MeasuremeKts.-Aperture '*- Zooecia ^32-0.36 mm. 



73=0.20 mm. 



Variations. The frontal is an olocyst absolutely smooth when there are no 

 areolae (fig. 21) ; it is covered with small granulations of pleurocystal origin when 

 very small, scattered areolae appear. More often there is only an oral avicu- 

 lariuni; it is small, elliptical, without pivot on the ordinary zooecia (figs. 19, 20) 

 but elongated, thin, with pivot on the ovicelled- zooecia; moreover, on the latter 

 it changes place, is removed from the aperture and becomes frontal (fig. 21). 



The ovicell is globular, salient, and bears in front a fragile finely ribbed 

 callosity of olocystal origin; it is bordered by a very thick circular collar. The 

 aperture of the ovicelled zooecia is larger (Za=0.10 mm. instead of 0. 07 mm.). 



The aperture is oblique, which, on account of perspective, diminishes the length 

 of the rimule. 



Affinities. This species differs from Stephanosella (Schizoporella) biaperta 

 Michelin, 1845, living and fossil, in the position of the avicularium. which is always 

 placed below the aperture, and in its smaller micrometric dimensions. 



It differs from Stephanosella parvipora in its larger aperture and in the 

 avicularium, which is placed below the aperture. 



Occurrence. Vicksburgian (Marianna limestone) : West bank Conecuh River, 

 Escambia County, Alabama (common) ; Claiborne, Monroe County. Alabama 

 (rare) ; 1 mile north of Monroeville, Alabama (very common). 



Geological distribution. Chattian of Germany (Reuss) and Tortonian of 

 Austria-Hungary (Reuss). 



Plesiotypcs.Cat. No. G42G9, U.S.N.M. 



Genus LACERNA Jullien, 1888. 

 188S. Lacerna JULLIEN, Mission Scientifiqne du Cap Horn, p. 48. 



The ovicell is hyperstomial and is provided with a special orifice, which can 

 be closed by the operculum for the passage of the eggs. The aperture is arched 

 anteriorly; its proximal border is straight, with a small, rounded rimule. The 

 nperture and the rimule are surrounded by the same peristome, which is provided 

 with spines. There is a vestibular arch. The frontal and the ovicell are formed 

 df an oloc3 T st surrounded with areolae, above which an incomplete and granular 

 pleurocyst is deposited. 14 tentacles. 



Genotype. Lacerna hosteenxis Jullien. 1888. 



Ranr/e. Lutetian-Recent. 



