John Croumbie Brown

He furthered his botanical studies, and in April 1853 took up the post of lecturer in botany at the Joint Medical School (King's College, Aberdeen), also being awarded the degree Doctor of Laws there in 1858.

In April 1863, following the death of Karl Wilhelm Ludwig Pappe, Brown took up the post of Colonial Botanist at the Cape, his duties including that of professor of botany at the South African College.

His reports also touched on agricultural issues, such as diseases in fruit trees, rust, manuring, the cultivation of various crops, experimental farms, irrigation, and Cape wines.

His 1863 report included the first official record of "krimpsiekte" or Cotyledonosis in small stock, particularly goats, caused by three genera of the Crassulaceae (Cotyledon, Tylecodon and Kalanchoe).

Some South African botanists were critical of Brown's contributions to botanical knowledge, but the noted Irish botanist William Henry Harvey singled out Brown for praise in the preface to Volume 3 of the Flora Capensis "for his unremitting kind attention to the interests of this work, and for the zeal which he has shown, since his appointment, in endeavouring to promote the study of botany in all parts of the Colony, and among the neighbouring extra-colonial missionaries".