NORTH AMERICAN EARLY TERTIARY BRYOZOA. 565 



Adeonellopsis distoma Busk, 1S58. Atlantic. 



Adeonellopsis (Eschara) coscinophora Reuss, 1847. Oligocene of Germany. 



Adeonellopsis wetherelli Gregory, 1892. 



ADEONELLOPSIS POROSA, new species. 



Plate S, fig. 13. 



The specimen figured is the only one which has been found. It incrusts 

 a shell. It is characterized by_ its large cribriform area, perforated by a dozen 

 pores. It is possibly the base of a bilamellar zoarium. 



Occurrence. -Wilcoxian (Bashi formation) : Woods Bluff, Alabama (very 

 rare). 



Holotype.CsA. No. 63813, U.S.N.M. 



ADEONELLOPSIS MAGNIPOROSA, new species. 



Plate S, figs. 14-20. 



Description. The zoarium is bilamellar; the fronds are wide and lobed. 

 The zooecia are distinct, elongated, elliptical, much narrowed toward the back, 

 separated by a deep furrow. The peristomice is transverse and semielliptic. The 

 cribriform area is deep and perforated by large stellate pores. The median avicu- 

 larium is triangular or orbicular, without pivot or denticle. 



Measurements. Zooecia |'Z.s=0.45-0.55 mm. Zooecia |Z^=0.50 mm. 



(exterior) 1^=0.25-0.30 mm. (interior) 1^=0.20 mm. 



Total area: Z=0.25 mm. 

 Width of apertura=0.09mm. 



Variations. The normal, adult zooecia have a transverse, semilunar, external 

 apertura below which is a rather large, elliptical arid oblique avicularium. The 

 cribriform area is deep and contains from five to seven stellate pores (figs. 16, 20). 



On old zooecia there is produced a strong pleurocystal incrustation in conse- 

 quence of which the avicularium and the cribriform area become buried. Then the 

 apertura, the avicularium, and the area are only visible in a single total area ; the 

 avicularium becomes triangular and pointed (fig. 15). Sometimes on the old 

 zooecia there is an adventitious, round avicularium (?) below the total area 

 (fig. 17). 



In spite of the considerable variations of the exterior, the internal aspect 

 (fig. 18) is, on the contrary, very constant, and in it are revealed the true charac- 

 ters of the species. 



Affinities. The new species differs from. Adeonellopsis wetherelli Gregory, 

 1892, which it much resembles in the large size of the pores of the cribriform area. 

 As this character is very constant we are obliged to give it specific importance. 



This is also the American species which has the largest ascopores. 



Occurrence. Wilcoxian (Bashi formation) : Woods Bluff, Alabama (com- 

 mon). 



Cotypes.Ca.i. No. 63830, U.S.N.M. 



