640 Report of the State Geologist. 



Family Actinotrypidae. 

 Actinotrypa, Ulrich. 

 (Geol; Sur. 111., Yol. YIII, p. 386. 1890.) 

 Type, Actinotrypa peculiaris^ Ulrich. 



" Zoaria very much as in Dichotryfa. Zooecial apertures show- 

 ing the ends of from eight to ten vertical septa-like ridges, which 

 extend down the inner side of the vestibule, nearly or quite to 

 the primitive apertures." (Uleioh.) 



The structure of the cell tubes precludes placing this genus 

 under either STioTorosiDiE or Ctstodictyid^. 



» 



98. 



■m 



mi' 



Fig. 97. Actinotrypa peculiaris, portion of the surface, x9. 



Fig. 98. A still further enlargement, xl8. 



Fig. 99. A transverse section, showing the structure of the zoarium a short distance from the 

 surface. 



Family Rhinoporidae, Ulrich, emend. 



Rhinopora, Hall. 



(Pal. N. Y., Yol. II, p. 170. 1852.) 



Type, Bhinopora verrucosa, Hall. 



Zoarium consisting of lamellate or subpalmate fronds, which 

 are cellulif erous on both sides. The outer edges are thickened 

 and celluliferous, and the entire surface on both sides is uni- 

 formly tuberculous. The tubercles (monticules) are usually 

 smooth and solid at their summits, rarely celluliferous ; surface 

 also exhibiting slender, rounding, bifurcating ridges, which 

 when the zoarium is a little worn, appear as shallow grooves ; 

 cell apertures nearly circular, occupying the summits of prom- 

 inent papillae, arranged in more or less regular intersecting lines ; 

 Jnterapertural space smooth ; intercellular space occupied by 

 mesopores. 



