Plate, draft of 'Internal view of the abdominal muscles of the boa constrictor' by William Clift Ink and grey watercolour drawing of an internal view of the abdominal muscles of a boa constrictor by William Clift. This work is a draft of the final version of this plate found at PT/7/27i/2. Subject: Zoology Published in Philosophical Transactions as 'Observations intended to show that the progressive motion of snakes is partly performed by means of the ribs'. Read 27 February 1812. [1812]