“The illustrations in this book have been drawn direct by the Author on `Plastocowell’ a transparent plastic material used in lithography and lithographed in Great Britain by W. S. Cowell Ltd at their Press, The Butter Market, Ipswich.” [p.2].
Orlando (the marmalade cat) is the subject of the series (of the same name) of 19 illustrated children's books written by Kathleen Hale between 1938 and 1972.
References
Hahn, Daniel (26 March 2015). The Oxford Companion to Children's Literature. Oxford University Press. p. 433. ISBN 9780199695140.
Carey, Frances & Tempest-Radford, Hugh, Plastocowell and Orlando the Marmalade Cat. Print Quarterly, Vol. 19, No. 3 (September 2002), pp. 278-280.