Paper, 'On the genus Ocythoë' extracted from a letter from Thomas Say to Wm [William] Elford Leach Subject: Zoology Published in Philosophical Transactions as 'On the genus Ocythoë; being an extract of a letter from Thomas Say, Esq. of Philadelphia, to Wm. Elford Leach, M. D. F. R. S'. Read 4 February 1819. Abstract published in Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London [later Proceedings of the Royal Society of London], Volume 2, 1833. [1819]