Eminent and versatile Swiss-born American zoologist and geologist (1807–1873) who carried out much of his research as a longtime faculty member at Harvard, where he was also instrumental in building the university’s enviable natural history collection. Ink signature, “L. Agassiz,” on an off-white 3.25 x 2 lightly-lined slip clipped from the close of a letter. Affixed to a slightly larger off-white card. In fine condition. RR Auction COA.