Exception is taken to a Pristiograptus ludensis zone age for the lower Elton beds of Shropshire, England, as proposed by M. G. Bassett and J. H. Shergold, and definition of the base of the P. nilssoni zone as the base of the Ludlovian in the Welsh borderland is reconfirmed. (For reference to paper under discussion, see this Bibliography Vol. 32, No. 3, 15 E68-03093.)

You do not currently have access to this article.