He next investigated the Devonian rocks and fossils of the Bas-Boulonnais; and in 1839 accompanied Sedgwick and Murchison in a study of the older Palaeozoic rocks of the Rhenish provinces and Belgium, the palaeontological results being communicated to the Geological Society of London in conjunction with the Vicomte d'Archiac.
Slater collaborated with Gertrude Elles on the stratigraphy of the Lower Palaeozoic (Elles and Slater 1906) of Wales.
He has written several books and scientific papers on Palaeozoic vertebrates and contributed to the Tree of Life phylogeny project.
Stephen Kenneth Donovan FLS (born 3 June 1954) is a British paleaontogolist, who is at Palaeozoic and Mesozoic Macroinvertebrates, Nederlands Centrum voor Biodiversiteit - Naturalis (formerly Nationaal Natuurhistorisch Museum.