devil's finger

plural devil's fingers

1. A belemnite, any of various extinct species of cephalopod in the order Belemnitida.
2. The fossil remains of such a cephalopod.

   Bivalves, a type of Jurassic oyster, are known as ‘devil’s toenails’ and the bullet shaped belemnites, which look like dinosaur teeth and are the remains of a creature resembling a cuttlefish, are, locally, called ‘devil’s fingers’.

   2010 December 4, Ruth Campbell, “Out & about – Whitby's fossil hunter”, in Northern Echo, Darlington, England

   2 more examples

   LXXVI. Belemnites, a conical or fusiform stone, of brown radiating spar, […] Various names have been assigned to this fossil; many of which, derived from the ridiculous notions entertained by the vulgar, in the early ages, need only be mentioned. Such are, devil’s fingers, Spectrorum candela, and idæus dactylus, from their having somewhat the form of fingers

   1811, James Parkinson, Organic Remains of a Former World, page 122

   In the Middle Ages, when fields in the Norfolk chalk and Oxford clay outcrops of England were ploughed, they would appear after a thunderstorm. The myth soon emerged that they were thunderbolts. It is more likely that the heavy downpour had washed away the surrounding soil to reveal the fossils. Belemnites are also known as St Peter’s fingers, devil’s fingers and ghostly candles.

   2007 February 12, “Fossils: myths, mystery and magic”, in Belfast Telegraph, page 1

   Synonyms: fingerstone