British palaeontologist Thomas Davidson (1817-85) was born in Edinburgh and began his studies at the city’s university. Encouraged by German palaeontologist Leopold von Buch, he began to study brachiopod fossils at the age of twenty, and he quickly became the undisputed authority. He was elected fellow of the Geological Society of London in 1852, receiving the Wollaston medal in 1865. He became a Fellow of the Royal Society in 1857. Published between 1850 and 1886, this six-volume work became the definitive reference text on the subject. It includes more than two hundred hand-drawn plates and a comprehensive bibliography. This volume, the fourth of six, is the first of two supplements providing corrections to earlier volumes and detailing species discovered since the original volumes were published.