NORTH AMERICAN EARLY TERTIARY BRYOZOA. 733 



MECYNOECIA CORNUTA. new species. 



Plate 155, figs. 30-36. 



Description. The zoarium is a cylindrical and bifurcated Entalophora. The' 

 tubes are little distinct, convex, widened at their extremity, horn-shaped, little 

 narrowed at the base, slightly striated transversally ; the peristome is thin, elliptical, 

 very little salient. The ovicell is quite elongate, smooth, globular, salient; the 

 oeciostome is elliptical transverse, supported on a peristome. 



Diameter of the peristome 0.14 mm. 



M<-<IXII,'< mcnts. 



Distance, between the peristomes 0.60 mm. 



Separation of the peristomes 0.50-0.52 mm. 



Diameter of the branches 0.66 mm. 



Affinities, This species differs from Mecynoecia semota, in which the tubes are 

 also horn-shaped, in its peristome of 0.14 and not 0.12 mm., and in its lesser peris- 

 tomial distance (0.60 and not 0.90 mm.). 



It differs from Mecynoecia lunata in which the separation of the peristomes 

 is very similar in the thinner branches, never containing more than eight longi- 

 tudinal rows of zooecia, and in the absence of a salient thread between the tubes. 



Occurrence. Vicksburgian (Marianna limestone) : One mile north of Monroe- 

 ville, North Carolina (common) ; deep well, Escambia County, Alabama (very 

 rare). 



Cotypes.Csit. No. 65464, U.S.N.M. 



MECYNOECIA PARVITUBA, new species. 

 Plate 128, figs. 3-7. 



Description. The zoarium is a thin Entalophora, with six longitudinal rows 

 of zooecia. The tubes are small, little distinct, slightly striated transversally, 

 bent upward at their extremity, and terminated by a salient peristomie; the 

 peristome is thin, orbicular, oblique. 



Diameter of the peristome 0.10 mm. 



Measurements. 



Distance of the peristomes 0.60-1.00 mm. 



Separation of the peristomes 0.40-0.60 mm. 



Diameter of the branches 0.50 mm. 



Affinities. This small species is quite well characterized by its small peristomial 

 dimensions. It differs from Mecynoecia pusilla in which the diameter is identical 

 in its zooecial length, much more than 0.70 mm. It differs from Mecynoecia 

 elongatotuba in its still thinner branches and in its peristomial diameter of 0.10 

 mm. (never 0.12 mm.). 



Occurrence. Vicksburgian (Marianna limestone) : One mile north of Monroe- 

 ville, Alabama (common). 



Upper Jacksonian (Ocala limestone) : Old Factory, about 1| miles above Bain- 

 bridge, Georgia (very rare). 



Cotypes.Ca,t No. 65321, U.S.N.M. 



