322 DESCRIPTION OF CHALK CORALS. 
A perusal of the foregoing statements will necessarily raise doubts respecting 
the generic position of the chalk coral; and the difficulties are such as almost 
constantly occur, when an attempt is made to refer a secondary fossil zoophyte 
to an existing genus. It has nevertheless been deemed better to assign the cre- 
taceous Bryozoon, most imperfectly investigated, provisionally to Flustra, than 
to propose a new term, leaving to a competent authority, with ample means for 
inquiring into the characters of the whole of the Celleporide, living and extinct, 
the establishing of a final determination. 
The free specimens (figs. 9& 10) were either regularly bifurcated, or had lateral 
shoots ; and one of them (fig. 10) was tinged throughout light-red. The upper 
extremities of the finer example (fig. 9) were nearly perfect, and exhibited a few 
immature cavities consisting of strong side-walls, and partially formed upper 
surfaces. The cells along the sides of the lobes were occasionally of ample di- 
mensions though irregular in form, but others were very small and defective, and 
plainly unfitted for the reception of digestive organs. Within the area of the 
specimens, the shape, as before stated, varied considerably, and to the greatest 
extent in the one which was tinted. The regular cells (fig. 9 a) were pear-shaped 
with a flat or slightly convex surface ; and they had frequently a slight furrow- 
like depression at the foot of the projecting margin. Their position was nearly 
vertical in the middle of the lobes, but more or less inclined outwards nearer the 
sides. The interpolated, spindle-shaped cavities (fig. 9a) were numerous, filling 
narrow interspaces ; but they could not be regarded as the precursors of addi- 
tional rows’, and their aperture was centrally situated and elongated. The 
tinted example (fig. 10) seldom afforded regularly-formed cells, but instances were 
noticed, which perfectly agreed with the most symmetrical of figure 9; the ova- 
rian capsules were also similar, as well as the interpolated cavities ; but the pro- 
jecting boundary-ridges were generally replaced by discontinuous variable furrows. 
The incrusting specimen, fig. 11, differed not as respected the normal and 
abnormal characters of the cells, or the nature of the ovarian capsule from the 
lobed. ‘The line of growth had extended in every direction so as to envelope 
completely the body to which the coral was attached ; and from mutual inter- 
ference, want of space or inequalities in the subjacent surface, the deviations in size 
and outline of the cells were innumerable. There were also many proofs of layers 
which extended over others; also instances of knobs composed of concentric layers. 
‘ Consult Dr. Grant’s remarks on the arrangement of cells in £2. carbasea, Edinb. New Phil. Journ, 
vol. iii. p. 112. 
