NORTH AMERICAN EARLY TERTIARY BRYOZOA. 187 



small convex chamber. The hyperstomial ovicell is situated on the gymnocyst of 

 the distal zooeciuin. 



. | ho = 0.30-0.3-2 nun. . \Ls= 0.42-0.46 mm. 



.]/, .'A/m'wi>Hfs. Opesia 7 Zooecia, . 



1/0 = 0.16-0.18 mm. U2=0.26-0.30 mm. 



. I rfii>!f!t '.y. The large size of its frontal avicularium and its greater micromet- 

 ric dimensions clearly distinguish this species from x,- t ;,/,,,<-;'//<ir!a cookei, with 

 which it is associated. 



No trace of a scutum has been found, nor has a reason been obtained to explain 

 the opesial lamella shown on some zooecia. One of our specimens is a branching 

 segment showing, as determined by Waters some time since, that the articulations 

 are calcified in such cases. The dorsal is an olocvst with two separated layers 

 (fig. 11). 



This splendid species is named in honor of Mr. J. B. Milner, who has taken a 

 keen interest in the bryozoa in his preparatory work upon the Tertiary fossils be- 

 longing to the United States Geological Survey and the United States National 

 Museum, and who has found many specimens for our study. 



Occurrence. Vicksburgian (Marianna limestone): Salt Mountain, 5 miles 

 south of Jackson, Alabama (rare) : Murder Creek, east of Castlebury, Conecuh 

 County, Alabama (very rare) ; west bank of the Conecuh Eiver, 1 mile below 

 mouth of the Sepulga River. Escambia County. Alabama (common). 



Vicksburgian (Red Bluff clay) : ~| miles southwest of Bladen Springs, Ala- 

 bama (rare). 



Cnt. Nos. 64238-642-40. U.S.N.M. 



SCRUPOCELLARIA RESSERI, new species. 



Plate SI. figs. 20-23. 



Description. The segments are formed of at least 10 alternating zooecia. The 

 zooecia are distinct, with or without an elliptical gymnocyst; the opesium elliptical; 

 mural rim is salient, thick, rounded, and bears two distal spines; the distal avicu- 

 larium is very large and triangular; the frontal avicularium is smaller, projecting 

 its pointed end above. On the dorsal the zooecia are distinct and convex; the 

 vibraculum is straight, salient, and provided with a rectilinear groove. The ovicell 

 is hyperstomial and situated on the distal zooeciuin. 



Measurements. Opesia 



7<o=0.20 mm. . |Z.z= 0.34-0.40 mm. 



ma 



7o=0.10-0.12 mm. 1/3=0.22-0.23 mm. 



Hnities. This species differs from both Scrupocellana cookei and /?. milneri 

 in the rectilinear groove of its vibraculum which gives it a false resemblance to 

 Caberea. The specific name is in honor of Mr. Charles E. Resser, of the United 

 States National Museum, who has been of assistance to us in the preparation of 

 the illustrations for this work. 



Ocoii'i'/iiri. Vicksburgian (Gleudon member of Marianna limestone): West 

 bank of the Conecuh River. 1 mile below the mouth of the Sepulga River, Escambia 

 County. Alabama (common). 



Cotypes.Cat. No. 6424i>. I'.S.X.M. 



