NORTH AMERICAN EARLY TERTIARY BRYOZOA. 



369 



Affinities. The form of the aperture is rather indeterminate; it is impossible 

 to say whether this species belongs to the Schizoporellae or to the Hippoporae. 



It resembles for this reason Cellaria schreibersi Eeuss v 1869, of the Priabonian, 

 but differs from it in the form of its zooecia, which are very thin in the posterior, 

 in their great length, and in its incomplete tremocyst. 



It differs from Tetraplaria tuberculata, not only in the form of its orifice, but 

 in the replacement of the two lateral tubercles by two small avicularia. 

 'i nee.- Middle Jack- 



sonian: Baldock, Barnwell County, 

 South Carolina (rare). 



Cotypes. Cat. No. 64071, 

 U.S.N.M. 



Genus GEMELLIPORA Smitt, 1872. 



1S72. Gem eUipora SMITT, F 1 o r i il a n 

 Bryozoa, pt. 1, Kongl. Svenska 

 Vetenskaps-Akaderniens Hanrt- 

 lingar, vol. 10, No. 11, p. 33. 



The opercula are subtriangu- 

 lar with two small lateral projec- 

 tions, corresponding with two small 

 lateral teeth in the apertura; the 

 muscular attachment is close to the 

 side of the operculum. The aper- 

 tura of the ovicelligerous zooecia 

 differs in shape from that of the 

 ordinary zooecia, in most species be- 

 ing wider with a flatter sinus. 

 (After Waters, 1904.) 



Genotype. Gemellipora gldbra 

 Smitt, 1872. 



Range. Miocene-Recent. 



This genus requires further ex- 

 amination. 



The recent species are : 



Gemellipora (Schizoporetta) 



triangula Hincks, 1881. 



Gemellipora (Lepralia) arrogata Waters, 1879. 

 Gemellipora (ScMsoporetta) fata MacGillivray, 1882. 

 Gemellipora glalra Smitt, 1872. 

 Gemellipora protitsa Thornely, 1905. 

 The fossil species are: 



Gemellipora eler/antissima MacGillivray, 1904. 

 5589O -JO Bull. 106 24 



FIG. 111. Genus Gemellipora Smitt, 1ST-'. 



A. Gemellipora r/labra Smitt, 1872. Zoarium, natural 

 size, and zooecia, enlarged. (After Smitt, 1872. i 



B-D. Gemellipora protusa Thornely, 1905. B. Ovi- 

 celled zooecia, X 25. C. Interior of a zooecium, show- 

 ing the oral aperture, X 85. D. Operculum, > 

 (B-D after Waters, 1913.) 



E. Gemellipora triangula Hincks, 1SS1. Operculum, 

 X 85. (After Waters, 1887.) 



F. Gemellipora arrogata Waters, 1879. Operculum, 

 X 85. (After Waters, 1904.) 



