LEPRALIA. a21 
the mouth there is, on each side, a single fine spine, which 
may be compared, perhaps, to a cat’s whisker. The pat- 
tern of the ornamented centre will be best understood by a 
reference to the Plate. In the middle of all there is a knob 
or projection (more or less obvious in different individuals), 
and round this ‘umbo-like projection’ there is a circle of 
small dots or punctures. From this circle emanate rays, 
or raised lines, between each of which is to be found a dot 
or puncture, larger in size than those of the other circle. 
These rays and stars, as they may be called, are alternate, 
and so form a circle outside the circle that surrounds the 
umbo. Dr. Greville discovered that the pear-shaped ter- 
mination of each cell is delicately fluted, as represented in 
the Plate; but this character cannot be considered a uni- 
versal guide, as the pear-shaped termination to the cell is 
wanting in many specimens, perhaps from the overcrowd- 
ing of the cells. 
The species has been found, during two successive winters, 
at Sidmouth (1851 and 1852), and is to be met with also 
in Jersey. 
Genus XIV. MEMBRANIPORA, Blainville. 
Gen. Char. Polypidom incrusting, membrano-calcareous, 
