Diagram, 'Diagram of the intra-palleal sinus-system of Terebratula' by William B [Benjamin] Carpenter A diagram in red and black ink and pencil, labelled figure 1, illustrating the the intra-palleal sinus-system of Terebratula, 'with its caecal prolongations into the shell'. A seection of valve, inner layer of mantle and outer layer in contact with the shell are labelled. Subject: Zoology 1854