/ 
73 * 
PENTAMERUS. 
Gen. Char. An equal-sided inequivalved bivalve, 
one valve divided by a longitudinal internal 
septum into two parts, the other by two septa 
into three parts or valves. Beaks incurved, 
imperforate. 
PENTAMERUS Knightii. 
TAB. XXVIII . — Upper Figure. 
Spec. Char. Circular, with many longitudinal 
furrows ; tripartite valve much depressed, with 
a short slightly-incurved beak ; bipartite valve 
conical, gradually produced into a long in- 
curved beak. 
A he septa in the flat valve extend to its edge, they are 
near each other and parallel. The septum in the other 
valve divides the beak ; the divisions extending to the edge 
of the shell, form a kind of double beak, much resembling 
the horny part of the toes of a pig’s foot, and leave an 
angular hollow within the curve ; the sto e that fills this 
hollow commonly separates easily, and may at first sight be 
taken for a third valve of a triangular carinated form. 
The edge of the deep valve appears to extend over that 
of the flatter one ; the length of the curve from the apex 
to the edgq is often six inches. 
About half a mile up the river Teme, near Downturn 
castle, the dell is bounded by two steep rocks approaching 
