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 ampullate 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. lxvi, 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. lxvi, figs. 5, 6. 
Reptaria, Rolle (Leonhard & Bronn, Neues Jahrbuch, p. 810. 1851). 
[Type, Reptaria stolonifera, Rolle.] 
Zoarium parasitic, procumbent, attached for its entire extent; consisting of 
a rachis from which proceed laterally, at regular intervals, cylindrical cell 
