50 
is smooth, and is sufficiently thin to allow of the walls of the corallites to be distinctly traced / 
through it. In such cases, the mouth or calice of the corallites appears to be closed with a 
kind of disc, which is sometimes level with the general surface, often depressed slightly below 
it, and sometimes elevated in the form of a rounded boss. ' 
In a very large number of specimens, the epitheca has been more or less denuded over 
parts where it originally existed. In such cases, it is mostly only the epitheca which has 
been removed, and the corallites are left intact and uninjured, with their calices quite empty. 
In other cases, the epitheca has been entirely decorticated, whilst the corallites may remain 
uninjured, or may be more or less broken away towards their outer ends. Such specimens 
can in general be readily recognized by the general shape of the colony end the peculiar char- 
acters of the corallites. In other cases, lastly, the epitheca is sufficiently thick to render the 
calices of the corallites below, obscure or invisible. In these instances, concentric lines of 
erowth are usually exhibited by the epitheca, and these are sometimes developed into such 
strong and irregular annulations as to simulate pretty closely the appearance of perfect speci- 
mens of Clisiophyllum Oneidaense (Billings). , 
The corallites radiate from the imaginary axis of the colony, either in straight lines or 
curves ; and the size of the mass in the turbinate specimens increases rapidly by the inter- 
stitial addition of fresh corallites. In shape the corallites are rounded, sub-prismatic, or, more 
commonly, distinctly prismatic. In size they are by no means uniform, there being generally 
a considerable number of under-sized corallites intercalated amongst the nearly equal-sizea 
larger tubes. The larger corallites have most commonly a diameter of from a line to a tenth 
of an inch, whilst the smaller ones may be half a line or less in width. 
The tabulz are commonly complete, sometimes incomplete, and are about three or four 
in the space of a line. 
The mural pores, so far as I have observed, are uniformly in single rows, placed on the 
flat surfaces of the corallites, not surrounded by an elevated border, and of comparatively 
large size. Their distance apart is most commonly about half a line, but is sometimes as 
much as a line, 
The walls of the corallites are of unusual thickness, in the great majority of cases; and 
they are not undistinguishably fused with those of contiguous corallites. Hence the lines of 
division between the walls of neighbouring tubes can be plainly seen in parts from which the 
epitheca has been removed, or even through the epitheca when the latter is of no great thick- 
ness. 
Completely decorticated specimens might very readily be referred to one of the two 
groups of forms usually placed in F. basalticu (Gold.); the group, namely, comprising forms 
with prismatic eorallites of small size, with but a single row of cells. Specimens, again, exhibit- 
ing longitudinal sections, but not exhibiting the outer surface, would also, almost certainly, be 
referred to F. basaltica. In the former case, the thickness of the walls of the corallites, and 
their being generally quite distinct and not fused with one another, would usually suffice for 
their determination. In the latter case, a positive determination would probably be impossi. 
ble, unless some portion of the outer surface could be observed. 
Locality and Formation.— Common in the Corniferous Limestone of Ridgeway, Port 
Colborne, and other localities in Western Ontario. Also in the Hamilton Formation of the 
Township of Bosanquet.. 
FAVOSITES POLYMORPHA (Goldfuss), 
(Plate VII. Fig. 7.) 
Calamopora polymorpha (Goldfuss), Petref. Germ. Plate XX VII. figs. 2b, 2c. 2d, 3b, 3c 
ceet. exclusis). 
Corallum sub-massive or dendroid, often dichotomously branched, or reticulated ; dia- 
meter of branches varying from a little over a line to more than an inch. Corallites radiating 
in all directions from an imaginary axis, nearly at right angles or obliquely, more or less con- 
tracted internally and widening as they approach the surface. Diameter of corallites from half 
to three-quarters of a line in branches of half an inch across, often with smaller ones interca- 
lated. Calices in reality more or jess polygonal, but often rendered circular by the thickening 
of their walls. Mural pores in single series. 
