PLATE 50, 31. 
CORAL. CHERT AND LIMESTONE, 
FIG. 1, 2. 
ERISMATOLITHUS Madreporites (duplicatus) 
aggregatus, stirpulis scapiformibus cylindricis strlatis 
coadunatis, stellis margine dilatatis : centro subpro- 
lifero. S. p. 
Fossil coral. The original a Madrepore. Aggregate; the 
mass irregular, consisting of numerous scapiform stirplets, 
cylindric, longitudinally striated, coadunate and unequal, 
varying in size, from that of a small quill, to half an inch 
or more .In diameter. The cavity of each stirplet reticulated, 
terminating in a radiated aperture, or star; the margin 
dilated; the centre proliferous, bearing a smaller spread- 
ing, central, prominent star, which appears to be the 
commencement of a fresh stirplet, or a further elongation 
of the old one. 
Not uncommon in limestone ; but rarely found in a per- 
fect state. The specimen figured, from Bahewell. 
« 
Fig. 1. Shows the terminal spreading apertures. The 
lamellar stellated structure of the cavities is not well pre- 
served in this specimen : in other respects it is very perfect. 
The duplicated form of the star Is more evident and entire 
than in most other specimens which I have seen. 
