A LARGE COLONY OF FOSS'IL CORAL 
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give a volume of 2450 cubic feet and a surface area of nearly 
2000 square feet. 
The corallites are cylindrical, straight or slightly flexuose, 
closely aggregated, seldom more than one-half their own diame- 
ters apart. Contiguous stems adhere by mutual growth along 
their common line of contact; such connection once begun is 
rarely discontinued except through accident or near points 
where new corallites are introduced. An individual may be 
attached in this manner at any given level to two to six or 
more of its neighbors, depending on their relative sizes. This 
sort of attachment makes unnecessary such connecting processes 
between the corallites as are commonly found in species of 
Diphyphyllum or Syringopora, for example. Moreover, this 
mode of mutual support is effected without appreciable modifica- 
tion of the cylindrical shape of the stems while the amount of 
space between the corallites is reduced in much of the colony 
almost to a minimum and this space is filled (except where dis- 
solved out) by a fine-grained, buff, dolomitic matrix in which 
are a very few delicate fragments of minute brachiopods shells. 
At the contact of the larger and more firmly united corallites 
the epitheca is wanting and attachment is brought about by the 
intergrowth of the outer edges of the septa and the interlocking 
of the dissepimental tissue. The amount of overlapping of the 
circumference of one corallite upon that of its neighbor, as seen 
in cross section, seldom exceeds one-fourth the length of the 
corallite ’s radius. Other corallites are united by adhesion of 
the walls only and all intergradations between the two extremes 
may be seen. The corallites are from two to eight millimeters in 
diameter, the average being between four and five. Individuals 
have been traced for nearly a foot only to find them broken or 
covered over by their neighbors; that they were considerably 
longer than this seems reasonably certain. Multiplication is by 
lateral gemmation, — from one to three new individuals bud off 
from a given corallite at the same level and each turns abruptly 
to the common direction of growth and parallels the parent stem ; 
budding, on the whole, is rare for on a surface one foot square 
only five or six cases were observed. 
The internal structure of the corallites is in most cases well 
preserved although complete obliteration by a . dense filling of 
quartz is not uncommon. Septa, 18 to 22 in number, thin, and 
