24 AMERICAN FOSSIL BRYOZOA. [bull. 173. 



CcELOCLEMA Ulrich. 



Zoarium forming hollow branches, lined internally with a striated 

 epitheca; zooecia as in Ceramoporella, but with thicker walls. 



Genotype: Diamesopora vaupeli \J\i''ich=^ CWamopor a alternata 

 James. Ordovician. Four described and three new species. 



Anolotichia Ulrich. 



Zoarium ramose, digitate, laminate, or incrusting; zooecial tubes 

 long, subpolygonal, intersected b}^ remote diaphragms; lunarium ele- 

 vated at the surface, traversed by two to six minute, vertical, closely 

 tabulated tubes; mesopores sparingly developed. 



Genotype: Anolotichia jponderosa Ulrich. Ordovician. Two de- 

 scribed and three new species. 



Ceramophylla Ulrich. 



Zoarium erect, bifoliate, the two layers grown together back to 

 back; in other respects like Ceramoporella and Coeloclema. 



Genotype and only known species: Ceramophylla frondosa \]\i'\c\i. 

 Ordovician. 



Bythotrypa Ulrich. 



Zoarium massive or lamellate; zooecial tubes long, intersected by 

 thin diaphragms; apertures subovate, nearly direct, lunarium large, 

 well-raised; mesopores numerous, open at the surface, forming inter- 

 nally a A'ery loose vesicular tissue. 



Genotype: Flstulipora f laxata Ulrich. Ordovician. Two species. 



ScENELLOPORA Ulrich. 



Zoarium simple, pedunculate, under surface epithecated; upper sur- 

 face slightly concave and celluliferous; zooecial apertures occupy the 

 summits of low ridges radiating from the center. 



Genotype and only known species: Scenellopora radiata Ulrich. 

 Ordovician. 



Spatiopora Ulrich. 



Zoarium forming thin crusts, usually on Orthoceras; zooecia very 

 short, nearly direct; apertures irregular, with blunt spines at the 

 angles, no lunarium developed; elevated, elongated macule usually a 

 conspicuous feature. 



Genotype: Spatiopora asper'a Ulrich. Ordovician. Ten described 

 and seven new species. 



Family FISTULIPORID^ Ulrich. 



Zoarium massive, lamellate or ramose, showing on the surface at 

 irregular intervals maculae or monticules composed of clusters of vesi- 



