When I had the honour last year of presenting an apology for the unfinished state in which Mr. Hunter left the Croonian lecture, I laid before this learned Society the plan upon which he meant to proceed; but my mind was at that time unfitted to prosecute so arduous an inquiry. The progress Mr. Hunter had made in this investigation enabled him to prove the crystalline humour of the eye to be laminated, and the laminæ to be composed of fibres; but the use to which these fibres are applied in the œconomy of the eye he had not ascertained, although several experiments were instituted with that view: his opinion was certainly in favour of their being muscular, for the purpose of adjusting the eye to different distances by their contraction and relaxation.