John William Salter

[1] In 1842, he was employed for a short time by Adam Sedgwick in arranging the fossils in the Woodwardian Museum at Cambridge, and he accompanied the professor on several geological expeditions (1842–1845) into Wales.

He succeeded Forbes as palaeontologist to the survey and gave his chief attention to the Palaeozoic fossils, spending much time in Wales and the border counties.

He contributed the palaeontological portion to Andrew Crombie Ramsay's Memoir on the Geology of North Wales (1866), assisted Roderick Murchison in his work on Siluria (1854 and later editions),[3] and Adam Sedgwick by preparing A Catalogue of the Collection of Cambrian and Silurian Fossils contained in the Geological Museum of the University of Cambridge (1873).

[4][2] In the very early 1860's, while collecting fossils in South West Wales as part of his duties for the British Geological Survey, Salter was examining coastal exposures by boat around the St Davids peninsula and landed in the small inlet of Porth-y-rhaw, in the mistaken belief that it was Solva Harbour a short distance to the east.

In 1862, while investigating the eastern cliff section and in strata now known as the Menevia Formation (Rees et al., 2014, p. 73)[5] Salter discovered remains of one of the largest trilobites ever found (over 50 cm long) and which, in 1863, he named Paradoxides davidis after his friend David Homfray (1822–1893), an amateur fossil collector from Porthmadog, North West Wales.

The thyestidians (Thyestiida) are an order of bony-armored jawless fish in the extinct vertebrate class Osteostraci and including the poorly understood osteostracan genus Auchenaspis Egerton, 1857.