xvi SYNOPSIS OF GENERA. 



pores more or less numerous, sometimes surrounding the cell apertures. Inter- 

 cellular space occupied by septate tubuli. 



Examples: Callopora perelegans, pi. xii, figs. 10-17; pi. xxiii a, fig. 14. 



Callopora multiseriata, pi. xxv, figs. 6, 7 ; pi. xxvi, figs. 18, 19. 



Callotrypa, n. s. o. [Type, Callopora macropora. Hall.] 



Zoariuni ramose, solid. Cells tubular, arising from the center of the branch, 

 increjising by interstitial addition. Apertures oval or polygonal. Mesopores 

 minute. Inter-cellular space solid or with small tubuli destitute of septa. 

 Examples : Callopora {Callotrypa) macropora, pi. xi, figs. 25-29 ; pi. xxiii, figs. 

 15-19. 

 Callopora {Callotrypa) unispina, pi. xi, figs. 35-37. 



Ccelocaulis, n. s. g. [Type, Callopora venusta, Hall.] 



Zoarium similar to Callopora in general form and in the characters of the 

 cell apertures and inter-cellular structure, but growing in hollow stems, lined 

 with a concentrically wrinkled and finely striated epitheca. 



Examples: Callopora {Calocaulis) venmta, pi. xii, figs. 20-24; pi. xxiii a, figs, 

 1-3, 4 ? 5. 

 Callopora {Calocaulis) aculeolata, pi. xxvi, figs. 16, 17. 



Lichenalia, Hall (Pal. N. Y., vol. ii, p. 171. 1852). 



[Type, Lichenalia concentrica, Hall.] 

 Zoarium explanate or massive. Cells septate, arising from the epitheca ; 

 apertures circular or trilobate, sometimes operculate, often denticulate with 

 the posterior portion of the peristome arched and elevated. Interapertural 

 space smooth; intercellular space vesiculose, vesicles irregularly disposed or 

 more regularly superimposed, giving the appearance of walled septate tubuli. 

 Examples : Lichenalia ovata, pi, xxxii, figs. 1-8, 

 Lichenalia lunata, pi. xxxi, figs. 1-9. 

 Pileotrypa, s. o., Hall (Report of State Geologist for 1885, advance sheets. 

 Expl. pi. 30. 1886). [Type, Lichenalia denticulata. Hall.] 

 Zoarium, in its manner of growth and general character, similar to Lichenalia ; 

 but with the posterior portions of the peristomes strongly elevated, and arched 

 with distinct denticulations in the aperture, which in the course of growth 

 form two longitudinal striations along the interior of the cell wall. 



Examples: Lichenalia {Pileotrypa) denticulata, pi, xxvi, figs. 21, 22, 26; pi. 

 XXX, figs. 12-20. 

 Lichenalia {Pileotrypa) pyriformis, pi. xxxi, figs. 21-27, 



