Probably Conocephalum conicum although a recent paper by Szweykowski et al. (2005) has shown that there are two species of Conocephalum in Europe, both of which occur in Britain. These are the typical C. conicum (L.) Dumort. and a second plant which they described as a new species, C. salebrosum Szweykowski, Buczkowska & Odrzykosli. For more information see the British Bryological Society website http://rbg-web2.rbge.org.uk/bbs/bbs.htm.