NICKLES AND BASSLEK.] DIAGNOSES OF GENERA. 27 



Glossotrypa Hall. 



Zoarium tubular, cylindrical, hollow; diameter of tube 2 nun.; thickness of zoa- 

 riuni 0.40 mm. Cells tubular, with frequent narrow projections (semidiaphragms) 

 from the cell walls extending partially across the tube; two pseudosepta on one side; 

 cell apertures jialiform, very closely disposed, frequently in diagonally intersecting 

 rows, the surface presenting a reticulated appearance; aj)ertures with denticulated 

 lunarium; interapertural space elevated, forming ridges; frequently a prominent 

 node at the intersection of the ridges, sometimes a depression or pit; surface with 

 monticules which are laterally in contact, giving to the frond an annulated apjjear- 

 ance; intercellular space vesiculose.' 



We interpret the foregoing description to mean that the genus is 

 like Busko])ora, save that the lunarium is developed interruptedly in 

 the zooecial tubes. 



Genotype and only known species: Lichenalia ^x^Ufijrrriis Hall. 

 Devonian. 



Selenopora Hall. 



Zoarium incrusting; surface with circular maculas surrounded by 

 large apertures; zooecia tubular, oblique, surrounded by vesicular tis- 

 sue; apertures subcircular, with overarching lunarium and situated in 

 polygonal, vestibular areas formed by coalescing ridges traversing the 

 interspaces. 



Genotype: Lichenalia eircincta Hall. Devonian. Two species. 



Favicella Hall (Fistuliporidra Simpson). 



Zoarium lamellate, free or incrusting; surface with monticules sur- 

 rounded by slightly larger apertures; zooecia tubular, cylindi'icul, at 

 first prostrate and thin-walled, then bending rather a})ruptly and pro- 

 ceeding almost direct to the surface, surrounded })y regularly super- 

 posed vesicles having the appearance of tabulated mesopores; aper- 

 tures circular, with equally elevated peristome, but no lunarium, 

 situated in polygonal vestibular areas formed by coalescing angular 

 ridges traversing the interspaces; vestibular area surrounding the aper- 

 tures occupied by minute angular pits. 



Genotype: Thallostigriia incluMa Hall. Devonian. Two species. 



COELOCAULIS Hall. 



Zoarium ramose, hollow, inner surface a thin epitheca with transverse wrinkles, 

 and fine longitudinal striations; cells tubular, arising from the epitheca and i)arallel 

 with it for a short distance, then turning abruptly outward; apertures I'ircular or 

 oval, sometimes irregularly disposed, at other times in a more or less regular quin- 

 cunx order; peristomes thin, distinctly and equally elevated, usually smooth, 

 but sometimes with numerous nodes or spinules; intercellular space occupied by 

 irregularly disposed vesicles, or by regularly superimjxjsed vesicles, resembling tabu- 

 late mesopores; interapertural space occupied by minute angular pits.^ 



Genotype: Callopora venusta Hall. Silurian, Devonian. Three 

 species. 



1 Simpson, Fourteenth Ann. Rop. State (ieologist New York for tlie year 1S94, p. '^>1. 



2 Ibid., p. 5.5^. 



