136 PALEOZOIC PALEONTOLOGY. 
The disk itself composed of vertical rods or spicules, with their ex- 
tremities expanded and more or less flattened to form the two sur- 
faces of the disk. The shafts of the spicules are cylindrical, about 
1 mm. or slightly more in thickness, and separated from each other 
by interspaces about equal to their own thickness. The arrangement 
of the terminations of the spicules upon the surface of the disk is 
in curved, radiating lines, crossing after the manner of the engine- 
turned ornamentation of a watch. The expanded outer extremities 
of the spicules are rhomboidal in outline, leaving narrow, linear inter- 
stices on each side between adjoining spicules. A short distance above 
the flattened, rhomboidal extremity there are four connecting pro- 
cesses, which join the spicule with each of the adjoining ones. The 
inner extremities of the spicules are also expanded and joined to- 
gether to form the inner surface of the disk. 
Remarks.—Specimens of this species of Receptaculites are not un- 
common in the lower beds of the Trenton limestone in New Jersey. 
The manner of preservation is always such as to exhibit poorly the 
structure of the fossil, as they can usually be detected only upon 
weathered surfaces of the rock, and are usually but fragmentary speci- 
mens. The largest specimen observed has a maximum diameter of 
100 mm., but it is only a fragment, and, when complete, must have 
been at least 200 mm. in diameter. 
ANTHOZOA. 
STREPTELASMA CORNICULUM Hall. 
Plate VI., Figs. 6-7. 
1901. Streptelasma corniculum Lambe, Cont. to Can. Pal., vol. IV., 
pt. Liep. 108, pls 6, figs. (7 b: 
Description—‘Corallum simple, elongato-conical, curved, gradually 
increasing in size from a pointed base until a maximum breadth of 
about 3 cent. is reached in a length of between 6 or 7 cent., average 
size somewhat smaller. Outer surface marked transversely by accre- 
tion ridges of rather variable size and disposition. Epitheca com- 
plete, with distinct septal furrows. Calyx moderately deep, with 
