61 
the growth lines; also in some of the valves the ribbing shows 
a subpustulose tendency; the posterior margin is finely 
laminae much produced; sinus broad and lobed. 
irdle.—In drie ecimen 8 mm. wide in front, or 
without the flattened appendages, 5 mm. in front and half 
that width behind, cleft for half its width at tail, very closely 
eset with solid, irregular, minute scales. But the most 
one of a white stiletto, but they are too broad to be described 
by that term, and may be better described as sharply-pointed 
white cylinders or spear-heads, which are at their base twice the 
thickness of the hair to which they are attached. These strange 
white spicules are clustered thickly at the base of and along the 
centres of the flattened finger-like processes, before referred 
to; these are sessile, rising straight out of the girdle. ere 
seems to be some relation between these spicules and the 
protruding portions of the girdle, as they and the hairs to 
which they are attached are only present opposite these. There 
are a few scattered about the girdle not in the main double row. 
easurements.—The specimen described in the ewig 
is 67x41 mm. Another, taken at the same time, now in Mr. 
o 
