28 
Calice moderately deep, with about sixty septa at a diameter of fourteen lines. The septa 
are unequally developed, and extend to the centre of the calice, where they are usually more 
or less twisted, and are sometimes elevated in the form of a. central boss. Arched septal 
strize and spines from a third of a line to half'a line apart. Some individuals appear to be 
simple, but most increase by the production of lateral buds, which spring from the parent 
corallite in an obliquely ascending manner. The epitheca exhibits nnmervus encircling striz 
and annulations of growth. 
H. proliferum is readily distinguished from the other species ofthe genus, by its elongated 
eylindrical form ; its increase by lateral gemmation, and its social habit. Not only is the species 
composite, in thesense that most of the individuals produce lateral buds, but, so far as I have ob- 
served, it is strictly social, vast numbers of individuals occurring together, growing vertically side 
by side butseparate. I have notseen more than one or twobuds borne by a single parentcorallite, 
and calicular gemmation appears to be unknown. The only other Heliophylinm known toincrease 
by lateral gemmation is H. sub-cespitoswm, but this is a very much smaller form, and is solitary 
in its habits. Detached individuals of H. proliferum in which budding appears not to have 
taken place, may usually be recognised by their great length and almost. strictiy cylindrical 
form, there being little or no increase of diameter as the cup is approached. Large indi- 
viduals have a length of seven or eight inches or more, with a calicine diameter of an inch 
and a half, and a similar diameter throughout. 
Locality and Formation.-—Extraordinarily abundant in one bed in the Corniferous Jime- 
stone of Ridgeway. 
21. HeLIoPHYLLUM ERIENsE (Billings). 
Heliophyllum Eriense (Billings) ; Canadian Journal, New Series, Vol. IV. p. 124. 
Corallum elongate, turbinate, straight or curved. Septa from seventy-four to one hun- 
dred and fifty in young and old individuals respectively. Septa extending'to the centre of the 
calice carrying on their sides delicate arched strize separated by intervals of from a quarter of 
a line to a sixth ofa line. Free edges of the septa “ denticulated with from five to seven short 
spines in the space of one line.” Hpithecawith sharp annulations and encircling ridges of growth. 
This species is readily distinguished by ‘‘ the closeness of the arched strize on the sides 
of the septa, and the minute denticulation on their free edges” (Billings). AH. Hriense is 
‘exceedingly variable in its dimensigns, varying in length from an inch and a half up to nearly 
a foot, and as regards the diameter of the calice from an inch and a quarter up to threeinches 
and a half. The calice is deep, and there appears to be an obscure septal fossula on one side. 
Locality and Formation.—Corniferous Limestone, Lot 29, Con. 3, Walpole ; and Port 
Colborne. Very rare, 
22. HELIOPHYLLUM COLLIGATUM, (Billings). 
(Plate V, Figs. 3, 3a). 
TTeliophyllum colligatum (Billings) ; Canadian Journal, New Series, Vol. IV. p. 126. 
“ Corallum forming large masses of long slender corallites, which are connected together 
at intervals of from two to four lines by periodic expansions of the cup ; radiating septa about 
fifty-two; diameter of the corallites where constricted five lines ; and of the expanded cup 
six to ten lines. Among the full grown there are interspersed some that are immature and of 
smaller size. The cup is shallow, the sides of the septa striated with from six to eight arched 
ridges in one line, and their free edges denticulated with the same number of minute spines. 
In the central area the transverse diaphragms are well developed, and sometimes constitute 
a pseudo-columella, which exhibits itselfin the shape of a small elevated boss in the centre of 
the cup” (Billings). 
This species cannot be confounded with any other. Itisremarkable amongst the typical 
species of this genus in being compound instead of simple ; and it has the tabulz unusually 
well developed, constituting a central area into which the septa, as a rule at any rate, do not 
enter. The epitheca is transversely ringed with annulations of growth, and, in the periodic 
expansions of the cup, with numerous fine encircling striae, which are crossed by the longitu- 
dinal lines which mark the position of the septa. As pointed out by Mr. Billings, H. coll 
gatum forms a transition between Heliophyllum and Phillipsastreea. 
Locality and Formation.—Corniferous Limestone of Rama’s Farm, Port Colborne, and 
‘Walpole. 
