CORALS AND BRYOZOA. 
195 
LICHEN ALIA, Hall. 1852. 
(See pages 30 and 77.) 
Lichenalia STELLATA. 
PLATE I.VI1I, FIGS. 15, 16. 
Lichenalia stellata, Hall. Trans. Albany Institute, vol. x, p. 1S3. 1881. 
“ • “ “ Report of State Geologist for 1883, p. 33. 18S4. 
Zoarium consisting of lamellate expansions, free or incrusting, or of masses 
formed by the superimposition of successive layers of growth; fronds varying 
in thickness from 1 to 5 mm.; under surface consisting of a thin epitheca, 
concentrically wrinkled, and with numerous fine, sharp, concentric striae, and 
also, by rounded, somewhat obscure, radiating lines. Cells tubular, recum¬ 
bent for a short distance, but for the greater portion of their length at right 
angles or oblique to the surface; walls thin, smooth or slightly wrinkled; 
septa moderately frequent. Intercellular tissue composed of vesicles; near 
the base these are large, irregular in size and arrangement, regularly super¬ 
imposed above, forming septate inter-cellular tubuli, septa numerous, fifty or 
sixty in the space of 5 mm. Cell apertures oval or slightly circular, 
diameter .35 mm., sometimes opening directly outward, but usually a little 
oblique to the surface, occasionally operculated, closely disposed, radiating 
from the maculae and frequently forming diagonally intersecting rows. 
Peristomes thick, anterior portion slightly elevated, posterior strongly 
elevated, oblique, smooth. Interapertural space smooth. Surface marked 
by prominent rounded monticules, the centres of which are distant about 
6 mm., and have an elongate depression destitute of cell apertures; the cell 
apertures immediately adjacent to the depressions radiate therefrom, and 
are larger than the others, having a diameter of .50 mm. The disposition 
of the cell apertures in rows radiating from the central depressions give to 
the monticules a stellate appearance. 
This species in its characteristic forms is easily recognized, but in some 
fronds there are variations, in which the resemblance to other species is 
greater : it most nearly resembles Fisiulipora operculata, but may be distinguished 
