Toadflax brocade moth  (Calophasia lunula)

Cocoon: a sheath of silk, which is spun around the pupae of some insects (a pupa is a stage in an insect's development, when huge changes occur that reorganise the larval form into the adult form. In butterflies the pupa is also called a chrysalis).
Pupal stage: Stage in an insect's development, when huge changes occur that reorganise the larval form into the adult form. In butterflies the pupa is also called a chrysalis.

1. UK BAP Species Action Plan (January 2002):
   http://www.ukbap.org.uk
   
2. Butterfly Conservation (January 2002):
   http://www.butterfly-conservation.org/ne/news/mww/
   
3. UK Moths (January 2002):
   http://www.ukmoths.force9.co.uk
   
4. Lyneborg, L. (1975) Moths in colour. Blandford Press, Dorset.
   
5. Skinner, B. (1984) Colour Identification Guide to Moths of the British Isles. Viking Press, London.
   
6. South, R. (1961) The moths of the British Isles. Frederick Warne & Co. Ltd., London.
   
7. Patton, S. (2002) Pers. comm.