Silurian Fossils 
lOI 
the periphery, probably at about those points where the walls of 
the corallites are pierced by the pores. 
Brownsport bed: glade northwest of the home of Charles 
McClanahan, two miles west of Vice Store, Tennessee. 
Chonophyilum (Craterophyllum) vulcanius. 
{Plate I, Fig. 12^ 
Resembles Chonophyilum canadense, Billings, as figured by 
Lambe in Revision of the genera and species of Canadian paleo- 
zoic corals, 1901. Corallum simple, width 65 mm.; base flat, cov- 
ered by concentrically wrinkled epitheca. Top fancifully com- 
pared with surface of a low volcano. . The vertical dimensions at 
the center are 10 mm.; at 6 mm. from the center of the corallum, 
15 mm.; at 17 mm. from the center, 4 mm.; toward the margin 
the corallum is reduced to a thin sheet. Septa represented at the 
base of the inner walls of the calyx or crater by about 74 vertical 
striations which increase in width toward the upper edge of the 
crater, continuing thence as low broad radiating plications increas- 
ing in width as far as the margin of the corallum. A narrow but 
distinct groove separates these plications along the extracalicular 
surface. There is no evidence of septa in the extracalicular part 
of the corallum, nor could any be detected in the central part. 
The radiating plications are evidently thin horizontally developed 
sheets, united along their adjacent edges so as to form a continu- 
ous expansion, radially grooved, covering the extracalicular surface. 
Corallum formed by the superaddition of successive expansions. 
Inner structure between successive expansions entirely vesiculose, 
composed of convex blister-like plates, irregularly arranged with- 
out reference to the radiating grooves traversing the expansions. 
On close inspection, the location of the blister-like plates may 
be detected on the upper surface of the expansions. Viewed from 
beneath, the grooves appear as raised lines, often crossing the 
concave surfaces of the blister plates. Structure of corallum not 
preserved at base of calyx or crater; no evidence of tabulae or of 
distinct septal plates in this part of the corallum. No distinct 
concentric striations on the upper, calycular, surface of the co- 
rallum. While probably congeneric with Chonophyilum canadense, 
this could not be determined from the specimen at hand. 
Brownsport bed: half a mile west of Dr. Evans’s, west of Hope 
creek, Tennessee. 
