XOKTH AMKKICAX EARLY TEKTIARY BRYOZOA. 1(39 



was articulated. The zooecia ^resents proximal punctations <>u ihe gynmocyst as 

 do certain specimens of St,nin-n<i< , ll,i in, iHnririiliiern. The present species di tiers, 

 however, in its cylindrical zoarimn and in its oppsiuin which is twice as small. 



Occwrrence. Lowest Eocene ( Hryozoan bed at base of Aquia formation) : Up- 

 per Marlboro. Maryland (very rare). 



IIolol //!>,. Cut. No. G3777. U.S.N.M. 



STAMENOCELLA MIDWAYANICA. new species. 



I'latc 4. tiu'. "-'.. 



Description. The zoarium is free, clavit'orin, articulated ( '.). compressed, 

 bilamellar, bearing on each face one to six longitudinal rows of zooecia. The 

 zooecia are much elongated, distinct, contracted at the back, separated by a groove 

 of little depth; the mural rim is flat, finely striated, enlarged at the base. The 

 opesium is elliptical or somewhat oval. The radicular zooecia are perforated by a 

 large round pore, and occur only at the base of the branches. The avicularium 

 which is placed in the middle of the gymnocy-t is cylindrical and very prominent ; 

 its orifice is oblique and turned toward the summit of the zoarinm. 



. (0=0.24-0.30 mm. . \Lz = (\:<u mm. 



.!/< aww< in, //,'.. Opesia , Zooecia 



|fo = 0.10-0.12 mm. {(3=0.20 mm- 



Affinities. The club-shaped fragments of this species were not necessarily 

 articulated, but unquestionably the zoarinm was provided with rootlets and its 

 fronds in growing away from the ancestrula became broader and broader. 



This species belongs to a group frequent in the Upper Cretaceous, which Canu 

 has classed in the artificial and unfortunately named division. Rh>/nchotclla, which 

 is distinguished from StamenoceUa only by the absence of known ovicells. As 

 the latter are very rare in our genus, and as the number of specimens is insufficient. 

 it is necessary to hesitate before founding another generic type. 



Our species differs from 3femb>'a>u/><n -n ( I-'hixt n lln }, ch/nc/ta D'Orbigny, 1852. 1 

 in its much smaller micrometric dimensions (Ls=0.50 mm. instead of 0.80 mm.). 

 The other species of the same group cited by D'Orbigny are very vigorous, robust, 

 and their zoarinm is at least five times larger, so comparison is not necessary. 



Occurrence. Midwayan (Clayton limestone) : Mabel vale, near Little Kock, 

 Arkansas (common); 1 mile west of Fort Gaines. Georgia (very rare): Luverne, 

 Crenshaw County. Alabama (very rare). 



< 'otypes.C&t. Xo. 63709. U.S.X.M. 



STAMENOCELLA ANATINA, new species. 



Plate 30, fig. 12. 



Description. The zoarinm is free and bilamellar: it is formed of large, flat 

 fronds; the two lamellae are inseparable and back to back. The zooecia are very 

 large, elongated, distinct, separated by a furrow: the mural rim i- little' salient, flat, 



1 Paleontologie Fr.inrn K.'. |i-u-;iii' ( 'rvtarc. Bi-yi^zonires. vol. 5. ] 11 



