THE DEVONIAN FOSSILS OF CANADA WEST. 265 
narrow, and somewhat angular in the bottom. These ridges are 
gently curved in crossing the broad flat margin of the cup. The 
depth of the central cavity is about one inch. A transverse or hori- 
zontal section shews that many of the septa (probably one-half of 
them) reach the centre. In a vertical section, extending downwards, 
so as to cut off the outer extremities of a few of the radiating 
ridges, it is shewn that the grooves on the floor of the cup indicate 
the position of the septa, and that the ridges are the interseptal 
spaces. The structure, as exhibited in this section, consists of ex- 
cessively thin, parallel, horizontal laminz (apparently from thirty to 
forty in the thickness of one line.) These lamin are arched up- 
wards between the septa, the curve corresponding with the con- 
vexity of the radiating ridges. In the lower part of the corallite, 
the interseptal tissue is much coarser. The surfaces of the ra- 
diating ridges appear to be covered with small tubercles. (See 
Pik &.) 
The only specimen of this truly magnificent coral that I have: 
seen, is imbedded in an upright position in the rock, the broad cir- 
cular dise of the cup (with the greater number of the rays well 
exposed by the action of the weather) being just on a level with: 
the surface of the stratum. The width of the dise or cup in, this 
individual is six and a half inches ; and it exhibits one hundred and’ 
twenty-five radiating ridges, which attain a breadth of about two. 
lines at the margin. It is highly probable that in other specimens 
the number of rays may be a little less or greater than it is in this 
one. The thickness of the piece of rock in which it is imbedded is 
three inches ; and on the under surface a transverse section of the. 
coral is exhibited, with a diameter of one inch and a half, and conse-- 
quently it expands from that size to a width of more than six inches: 
in the length ef three inches. At this rate of tapering, the total 
length of the perfect fossil must be about four inches and a half. 
Most probably a small portion of the pointed base is more or less 
curved. I have not seen the surface below the edge of the disc. 
This species resembles Chonophyllum perfoliatum (Goldfuss),, but 
is much larger, and has double the number of radiating septa. 
Locality and formation.—Lot No. 1, con. 14, Township of Wal- 
pole. . 
Collector.—J. De Cew. 
Vou. V. Vv 
