Buckman was the eldest son of
James Buckman (1814-1884), Professor of Geology, Botany, and Zoology at the
Royal Agricultural College 1848-1863, and his wife Julia (1834–1865). His first scientific paper (which related to Brachiopoda) was published in 1883, in the
Proceedings of the Dorsetshire Natural History Field Club. He was a prolific author. He showed that ammonites could be used as
index fossils to subdivide the Jurassic strata. His major work,
A Monograph of the Ammonites of the "Inferior Oolite Series" (never really completed), was published in several volumes by the
Palaeontographical Society 1887-1907. He
described numerous
genera and
species of marine
fossil. During his lifetime, he gained a reputation as a "
splitter". His obituary in
Nature says that through his studies he "was led to create a multitude of genera and species far beyond what had hitherto been deemed necessary". From 1897 to at least 1899, Sydney and his wife Maude were active in the early modern
feminist movement, promoting
practical clothing for women through organisations such as the Western Rational Dress Movement and Cycling for Women.{{cite web ==Posthumous reputation==