SYNOPSIS OF GENERA. xxv 



Ichthyorachis, McCoy (Carboniferous Fossils of Ireland, p. 205. 1844). 

 [Type, Ichthyorachis Newenhami, McCoy.] 



Bryozoum plumose, consisting of a rachis with short lateral branches or 

 pinnules; celluliferous on one side. Cell apertures in two ranges on the 

 branches, and in three or more on the main stem. 



Example: Ichthyorachis Nereis, pi. xxii, figs. 19-21. 



Crisinella, Hall (Report of State Geologist for 1882. Expl pi. xxvi, 1883). 



[Type, Crisina ? scrobiculata, Hall.] 



Zoarium ramose, solid, celluliferous on one face. Cell apertures arranged in 

 oblique, ascending rows from the center to the margin of the branch, peristomes 

 prominent. Interapertural space with large polygonal pits or mesopores. 



Example : Crisinella scrobiculata, pi. xxxiii, figs. 6-8. 



Cystopora, Hall (Trans. Albany Institute, vol. x, p. 161. 1881). 



[Type, Cystopora geniculata, Hall.] 



Zoarium consisting of an aggregation of ampuUate tubular cells, arising from 

 the center of the stipe or branch, enlarging about the middle of their length, 

 turning abruptly outward and much constricted at the aperture. Cell tubes 

 exposed for more than half their length. 



Example : Cystopora geniculata, pi. Ixvi, figs. 7-10. 



Clonopora, Hall (Trans. Albany Institute, vol. x, p. 162. 1881). 

 [Type, Clonopora semireducta, Hall.] 



Zoarium ramose, branches consisting of an aggregation of elongate, cylin- 

 drical, tubular cells, which at more or less regular intervals become entirely 

 free and turn abruptly outwards in an umbelliform expansion or in alternation. 

 Cell apertures expanded. 



Examples : Clonopora semireducta, pi. xvi, figs. 3, 4. 

 Clonopora incurva, pi. Ixvi, figs. 5, 6. 



Reptaria, Rolle (Leonhard & Bronn, Neues Jahrbuch, p. 810. 1851). 



[Type, Reptaria stolonifera, Rolle.] 



Zoarium parcasitic, procumbent, attached for its entire extent; consisting of 

 a rachis from which proceed laterally, at regular intervals, cylindrical cell 



